Length, m 0.2 0.3 0.4 0.5 0.6 0.7 Current, I A 11 AI g Repeat the procedure in c above for the values of lengths given. 5 marks www.freekcsepastpapers.comPage 261 h Calculate the value of 1 and record in the table above. 1 mark i On the grid provided plot a graph of I1 y- axis against l 5 marks j Determine the gradient of the graph. 2 marks k Given that, 1 , determine the value of . 3 marks QUESTION 2 You are provided with the following: - a metre rule - knife edge raised 20 cm above bench - one 50 g mass and one 100 g mass - a beaker or any container - some thread - some water in a beaker - Liquid L in a beaker - tissue paper - A triangular glass prism - A piece of soft board - Four optical pins - Four office pins - A sheet of plain paper PART A Proceed as follows: a Balance the metre rule edge and record the reading at this point .............................................................. cm 1 mark For the rest of this experiment the knife edge must be placed at this position b Set up the apparatus as shown in the figure below. Use the thread provided to hang the masses such that the positions of support can be adjusted. The balance is attained by adjusting the position of the 100g mass. Note that the distances X is measured form the knife edge and the 50g mass is fully submerged in the water. C Record the value of X . Cm ................................................... 1 mark d Apply the principle of moments to determine the weight Ww of the 50 g mass in water and hence determine the up thrust Uw in water Ww N ............................................. 2 marks Uw N ..............................................


Cm ................................................... 1 mark d Apply the principle of moments to determine the weight Ww of the 50 g mass in water and hence determine the up thrust Uw in water Ww N ............................................. 2 marks Uw N .............................................. 1 mark e Remove the 50 g mass from the water and dry it using tissue paper. F Maintaining the distance of 30cm in step d , now balance the metre rule when the 50 g mass is fully submerged in the liquid L Record the value of the distance X. cm ................................... 1 mark g Apply the principle of moments to determine the weight WL of the 50 g mass in the liquid L and hence determine the upthrust UL in the liquid i WL 2 mark ii UL 1 mark iii RD of liquid L 2 marks www.freekcsepastpapers.comPage 262 PART B Proceed as follows: a Place the plain sheet of paper on the soft board and pin it using the office pins at the comers. Trace the triangular prism outline of the prism on the sheet of paper use the upper part to leave space for two other outlines on the same page . Label the vertices of the outline at A, B and C. Remove the prism from the paper. B On the outline at a point O near the centre of side AB draw a normal ON. C Draw a line PO at an angle of 30 to the normal ON as shown in the figure below. D Replace the prism accurately on the outline. Fix two optical pins vertically on line PO at different points see the figure below . E View the images of the two pins through side AC of the outline. Fix a third and fourth pin vertically such that they are in line with the images of the first and second pin. Remove the prism and the pins. Draw a line joining the marks made by the third and fourth pins and extend it to join line PO also extended as shown below. Measure F, the angle of deviation of the emergent ray. 2 marks f Repeat part e for other angles of incidence shown in the table below.


Draw a line joining the marks made by the third and fourth pins and extend it to join line PO also extended as shown below. Measure F, the angle of deviation of the emergent ray. 2 marks f Repeat part e for other angles of incidence shown in the table below. Draw a fresh outline of the prism for each angle of incidence Complete table 1 3 marks Angle of incidence 30 50 70 Angle of deviation g Determine: i E the angle of emergence between the emergent ray and the normal at the point of emergence at the least angle of deviation. 2 marks ii K given that 2 sin 30 2 where F0 is the least angle of deviation 2 marks www.freekcsepastpapers.comPage 232 LUGARI JOINT MOCK EXAMINATION, 2023 Kenya Certificate of Secondary Education 232 1 PHYSICS PAPER 1 TIME: 2HRS INSTRUCTIONS TO CANDIDATES i Answer ALL the questions in section A and B. ii All working MUST be clearly shown. Iii Non programmable silent calculators may be used. Constant: g 10N kg or 10m s2 SECTION A: 25 MARKS 1. The figure below shows part of a vernier calipers when the jaws are closed without an object in between the jaws. A State the zero error of the vernier callipers. 1mark b A student used the same vernier calipers to measure the diameter of a test tube of actual diameter 2.15cm. What was the reading shown by the vernier callipers? 1mark 2. State a reason why a burn from steam at 1000C is more severe than a burn from boiling water at the same temperature 1 mark 3. Apart from temperature difference between the ends of a material, state any other two factors that determines rate of heat flow in a material 2marks 4. A point in the rim of a wheel has a linear velocity of 5.6 m s. if the rim has a radius of 40cm determine the angular velocity of the point 2marks 5. A wooden block of mass 2kg is placed on a horizontal surface.


A point in the rim of a wheel has a linear velocity of 5.6 m s. if the rim has a radius of 40cm determine the angular velocity of the point 2marks 5. A wooden block of mass 2kg is placed on a horizontal surface. A horizontal force of 12N is exerted on it makes it to accelerate at 5ms-2. Find the coefficient of friction between the surfaces. 3marks 6. Explain briefly how the temperature in a green house is kept higher than outside. 2 marks 7. The figure below shows two inflated balloons hanging vertically on light threads. State and explain the observation that will be made when a stream of air is blown in the space between the balloons. 2 marks 8. Explain why a hole in a ship near the bottom is more dangerous than the one near the top 1mark 9. The diagram bellow shows a uniform meter rule pivoted at its center and balanced by the forces shown. 3marks Determine the value of x. www.freekcsepastpapers.comPage 233 10. The figure shows a capillary tube dipped in water. State two differences that will be observed when water is replaced with mercury in the set up above. 2 marks 11. Give the transducer used to convert mechanical energy to electrical energy. 1 mark 12. A body is uniformly accelerated from rest to a final velocity of 100m s in 10seconds. Calculate the distance covered. 2marks 13. The figure below shows beaker containing a block of ice. State and explain the change in stability when the ice melts. 2marks SECTION B 55 MARKS 14. A Define the term heat capacity. 1 mark b A metal block of mass 2.0kg is heated electrically. The voltmeter read 12 volts and ammeter 4.0A. The temperature of the metal block increased from 250C to 750C in 10 minutes. Assuming no heat is lost to the surrounding. Determine: i Heat supplied by the heater. 2marks ii Heat gained by the metal cylinder 1mark iii Specific heat capacity of the metal block.


Assuming no heat is lost to the surrounding. Determine: i Heat supplied by the heater. 2marks ii Heat gained by the metal cylinder 1mark iii Specific heat capacity of the metal block. 2marks c Explain why food cooks faster in a pressure cooker than in an open sufuria 2marks d The figure below shows two identical containers A and B containing hot water and ice block. State with reason which water cools faster assuming that the wire gauge absorbs negligible heat. 2marks 15 a State Newton s second law of motion in terms of in momentum. 1mark b i A bullet of mass 20.0 g is fired with a velocity of 300m s into a wooden block of mass 4.98 kg suspended from a long in extensible string. The bullet sticks into the wood and the two moves together. Find the velocity of the block and bullet immediately after collision took place. 2marks ii Calculate the height to which both swings upwards. 2marks Water Capillary tube Ice block wrapped in wire gauze Hot Water Floating ice block B Awww.freekcsepastpapers.comPage 234 c Figure shows a hydraulic press system using a lever of negligible mass on the side of a small piston pivoted at point P. A force of 200N is applied at R. Calculate; i The force F exerted by small piston on the liquid. 2marks ii The weight of the Bale supported by the large piston 2marks iii Efficiency of the system. 3marks 16. A State Archimedes principle 1mark b A cylinder of length 5.0 cm and uniform cross section area 50.00 cm2 is suspended from a spring balance and totally immersed in water. If the density of the material of the cylinder is 1.25g cm3 and density of water is 1g cm3determine: i The up thrust on the cylinder 2marks ii Weight of the cylinder 2marks iii The reading on the spring balance 2marks c i State the reason why lead shots are fixed at the bottom of hydrometer.


3marks 16. A State Archimedes principle 1mark b A cylinder of length 5.0 cm and uniform cross section area 50.00 cm2 is suspended from a spring balance and totally immersed in water. If the density of the material of the cylinder is 1.25g cm3 and density of water is 1g cm3determine: i The up thrust on the cylinder 2marks ii Weight of the cylinder 2marks iii The reading on the spring balance 2marks c i State the reason why lead shots are fixed at the bottom of hydrometer. 1 mark ii A hydrometer of mass 30.0 g floats in water of density 1.0g cm3.If the bulb of the hydrometer had a volume of 2.8x10-5 m3 and stem has a cross section area of 1.0 cm2, what length of the stem would be submerged in the water. 3marks 17. A Define the term angular velocity. 1mark b The graph below was obtained from an experiment to investigate the variation of the centripetal force, F with the radius, r of the circle on which a body rotates was performed. From the graph, determine the angular velocity, of the body given that m 100g and F m 2r c where c is a constant. 3 marks c A stone of mass 40g is tied to the end of a string 50cm long and whirled in a vertical circle at 2 revolutions per second. Calculate the maximum tension in the string. 3marks d A stone is thrown horizontally with a velocity of 45m s from the top of a vertical tower 50m high. Determine: i The time taken by the bullet to reach the ground 2marks ii The maximum horizontal distance covered by the bullet 2marks P 100 cm 50 cm Liquid Area 180cm2 A Bale 200 N A 50 cm2 Rwww.freekcsepastpapers.comPage 235 18. A Define the absolute zero of the Kelvin temperature scale.


3marks d A stone is thrown horizontally with a velocity of 45m s from the top of a vertical tower 50m high. Determine: i The time taken by the bullet to reach the ground 2marks ii The maximum horizontal distance covered by the bullet 2marks P 100 cm 50 cm Liquid Area 180cm2 A Bale 200 N A 50 cm2 Rwww.freekcsepastpapers.comPage 235 18. A Define the absolute zero of the Kelvin temperature scale. 1 mark b The diagram below shows an experiment to investigate the relationship between volume and temperature of a fixed mass of gas at constant pressure i While stating any measurements to be made, explain how the set up would be used to verify Charles law. 3marks iii On the grid shown in the figure below sketch a graph of volume cm3 against temperature 0C for the experiment above. Clearly mark with the letter T the absolute zero temperature. 1 mark c A mass of air of volume 750cm3 is heated at constant pressure from 100 C to 1000 C. determine the final volume of the air. 2marks d The figure below shows a graph of weights of persons entering a lift against the extension of four similar springs supporting a lift. From the graph determine, i The spring constant of the springs 3marks ii The spring constant of a single spring 1mrk 600000.050.10.150.20.250.3Force, F N Extension,e m www.freekcsepastpapers.comPage 236 LUGARI JOINT MOCK EXAMINATION, 2023 Kenya Certificate of Secondary Education 232 2 PHYSICS Theory Paper 2 TIME: 2 HOURS INSTRUCTIONS: Answer all questions in section A and B. All working must be clearly shown. Mathematical tables and electronic calculators may be used. SECTION A 25 MARKS Answer ALL the questions in this section. 1. Two plane mirrors are inclined at an angle of 120o to each other such that their reflecting surfaces face each other. An object pins stands midway between the mirrors. Draw a ray diagram to show all the images 3mks 2. State two conditions necessary for the occurrence of an annular eclipse 2mks 3.


An object pins stands midway between the mirrors. Draw a ray diagram to show all the images 3mks 2. State two conditions necessary for the occurrence of an annular eclipse 2mks 3. The figure below shows two parallel rays incident on a concave mirror. F is the focal point of the mirror. Sketch on the same diagram the path of the rays after striking the mirror. 2mks 4. State the class of waves to which sound belongs 1mk 5. Calculate the value of the critical angle C shown in the figure below 2mks 6. In the diagram below, two electroscopes A and B carry same type of charges as shown. The two are then connected with a copper wire as shown State and explain the observations 2mks www.freekcsepastpapers.comPage 237 6. The figure below shows a real image I formed by a convex lens On the same grid, construct a ray diagram to locate the position of the object 2mks 7. State a property of electromagnetic wave on which the operation of a radar system is based 1mk 8. The figure below shows an attempt to supply each of the three lamps L1, L2 and L3 with a switch i Explain why this is a poor connection 1mk ii Redraw an adjacent diagram to show the best positioning for the switches 1mk 9. State one use of x-ray in medicine and one use in industry 2mks 10. Draw the magnetic field lines due to the configuration shown below 1mk 11. Sketch the current voltage characteristic of a junction diode in a forward bias mode 1mk 12. The graph below represents values of 1 f and corresponding values of wavelength for waves transmitted in a certain medium N S Soft iron 0 1 2 3 4 0.00 0.02 0.04 0.06 0.08 0.10 Wavelength, m 1 f Hz-1 www.freekcsepastpapers.comPage 238 From the graph, determine the speed of the waves 3mks 13. State one causes of power loss in long distance transmission wires and how these loses can be minimized 1mk SECTION B 55 MKS Answer all questions. 14.


1mk III. Explain how the radiation from the radioactive source is detected in the chamber. 2mks IV. State one advantage of the cold chamber over a charged gold leaf electroscope when used as detectors of radiation 1mk b The graph below shows how the activity of a sample of the radioisotope technetium which is used extensively in medicine, varies with time. I. Use the graph to determine the half-life, T of technetium 1mk II. Hence calculate the decay constant for technetium given that 6931.021 Twhere is the decay constant. 1mk III. Determine the number of technetium atoms remaining in the sample after 24 hours 1mk Felt soaked in alcohol Base of chamber Radioactive source Solid CO2 Form Transparent glass Lamp Time hours 0 2 4 6 8 10 12 14 16 18 20 22 24 0 1 2 3 4 5 6 7 8 Activity x 107 B2 www.freekcsepastpapers.comPage 240 16. The figure below shows the features of an X-ray tube a i What is the purpose of the oil going in and out of the anode 1mk ii State with reason the property of tungsten that makes it suitable as a target 1mk b An X-ray tube operates with a potential difference of 100kv and filament current is 20mA. Calculate; I. The power transferred to the target of X-ray tube 2mks II. The number of electrons hitting the target per second 2mks III. The maximum energy of X-ray produced Take charge of an electron 1.6x10-19C, mass of an electron 9.1x10-31kg, fmax 3 x 1019 Hz 2mks c The diagram shows monochromatic radiation falling on a photocell connected to a circuit The incident radiation has a wavelength of 2.15x10-7m. The metal surface of the photocell has a work function of 2.26 eV I.


The number of electrons hitting the target per second 2mks III. The maximum energy of X-ray produced Take charge of an electron 1.6x10-19C, mass of an electron 9.1x10-31kg, fmax 3 x 1019 Hz 2mks c The diagram shows monochromatic radiation falling on a photocell connected to a circuit The incident radiation has a wavelength of 2.15x10-7m. The metal surface of the photocell has a work function of 2.26 eV I. Calculate the energy in eV of a proton of the incident radiation Take speed of light C 3.0x108ms-1, Planck s constant, h 6.63x10-34JS and electronic charge, e 1.6x10-19C 3mks II. What is the maximum kinetic energy of the emitted electrons 2mks III. Write down the value of the stopping potential 1mk 17. A State Lenz s law of electro-magnetic induction 1mk b In the figure below, the bar magnet is moved out of the coil i If the current, I is induced in the coil in the direction shown, what is the polarity of x of the magnet? 1mk ii Explain briefly the source of electrical energy in the circuit 1mk c A hydro-electric power station produces 500KW at a voltage of 10KV. The voltage is then stepped up to 150KV and the power is transmitted through cables of resistance 200 to a step-down transformer in a sub-station. Assuming that both transformers are 100 efficient. Calculate; Vacuum Filament supply Tungsten target Copper anode x-rays Cathode Filament High p.d Variable d.c supply -6v to 6v Anode Incident monochromatic Photo cathode Motionwww.freekcsepastpapers.comPage 241 i The current produced by the generator 2mks ii The current that flows through the transmission cables 2mks iii The voltage drop across the transmission cables 2mks iv The power loss during transmission 2mks v The power that reaches the sub-station 2mks 18.


The voltage is then stepped up to 150KV and the power is transmitted through cables of resistance 200 to a step-down transformer in a sub-station. Assuming that both transformers are 100 efficient. Calculate; Vacuum Filament supply Tungsten target Copper anode x-rays Cathode Filament High p.d Variable d.c supply -6v to 6v Anode Incident monochromatic Photo cathode Motionwww.freekcsepastpapers.comPage 241 i The current produced by the generator 2mks ii The current that flows through the transmission cables 2mks iii The voltage drop across the transmission cables 2mks iv The power loss during transmission 2mks v The power that reaches the sub-station 2mks 18. A The following graph shows the variation of image distance, v, with magnification, for a converging lens. Using the graph and the equation 1 Mfv determine: i The object position when the image position is 45 cm 2mks ii The focal length of the lens 2mks iii The power of the lens 2mks b The following figure shows an eye defect Name the defect and illustrate on the same diagram how the defect could be corrected. 2mks Image distance 10cm www.freekcsepastpapers.comPage 242 LUGARI JOINT MOCK EXAMINATION Kenya Certificate of Secondary Education 2023 232 3 PHYSICS PAPER 3 Answer all the questions. I You are provided with the following: ii A watch glass iii A small piece of plasticine iv A marble v A stop watch vi Vernier calipers vii Triangular glass prism viii Four optical pins ix Some cello tape x A soft board xi A plain sheet of paper xii An electronic balance for sharing i Record the mass of the marble. .m 1mk a Place the watch glass flat on the table with a small piece of plasticine to fix it firmly to the bench at the one place it touches. Release the marble from one end of the watch glass and time 10 complete oscillations with a stop watch. Repeat these three times.


.m 1mk a Place the watch glass flat on the table with a small piece of plasticine to fix it firmly to the bench at the one place it touches. Release the marble from one end of the watch glass and time 10 complete oscillations with a stop watch. Repeat these three times. Time for 10 oscillation Periodic time T s 1 2 3 2mks Find the average periodic time 2mk b Measure the diameter of the marble with vernier calipers and hence find its radius. Diameter . 1mk Radius r 1mk c Determine the volume of the marble given that V 2mks d Calculate the radius of curvature of the watch glass R from the formula R-r 2mks Where g 9.8m s2 , 3.142 e Determine the density of the marble 2mks www.freekcsepastpapers.comPage 243 PART B f Fix the plain sheet of paper on the soft board using some cello tape. Place the triangular prism on the paper and trace its outline on the sheet of paper. Remove the prism and use a ruler to extend the three side of the outline. Measure angle A and the length l A 1 mk l 1 mk NB: The plain sheet of paper must be submitted together with the question paper. G At a point about a third way along one side of the outline from angle A, draw a normal. H Draw a line at angle i 400 to the normal. Stick two pins P1 and P2 vertically on this line as shown below. Place the prism accurately on the outline. By viewing through the opposite side, stick two other pins P3 and P4 vertically such that they are in line with the two images of pins P1 and 2. Measure angle D i For two other values of angle I shown in the table 2 locate and measure the corresponding angles of deviation.


A uniform meter rule pivoted at its 15cm mark is balanced by a 200g mass suspended at the 5cm mark. Determine the weight of the meter rule 3marks 5. A paper windmill in a horizontal axis was placed about a candle as shown in the figure. When the candle was lit the paper windmill began to rotate. Explain this observation. 2marks 6. An object was placed on an inverted bowl as shown. I State the type of stability above. 1mark ii Define the type stability above. 1mark www.freekcsepastpapers.com225 7. A pipe of diameter 12mm is connected to another pipe of radius 9mm. If water flows in the wider pipe at the speed of 2m s what is the speed in the narrow pipe. 3marks 8. A car starting from rest accelerates uniformly for 5minutes to reach 30m s. It continues at this speed for the next 20minutes and then decelerates uniformly to come to stop in 10 minutes. On the axes provided sketch the graph of velocity against time for the motion of the car 1mark 9. A diver was swimming in a swimming pool of uniform depth of 0.8m from the surface of water. If atmospheric pressure acting on the surface of water is 103000pa calculate the total pressure experienced by the diver. Density of water 1g cm3, g 10m s2 2marks 10. The boiling point of water is known to be at 100oC. A student heated some water and noticed that it boiled at 101oC state two possible reasons for this observation. 2marks 11. Explain the difference between a liquid and a gas in terms of intermolecular distance and force. 2marks 12. State the source of energy for gases in the atmosphere. 1mark SECTION B 55 MARKS 13. A Define the term velocity ratio of a machine 1mark b Figure below shows part of a hydraulic press. The plunger is the position where effort is applied while the ram piston is the position where load is applied. The plunger has a cross-section area a m2 while the ram piston has a cross-section area Am2. When the plunger moves down a distance d, the ram piston moves up a distance d.


The plunger is the position where effort is applied while the ram piston is the position where load is applied. The plunger has a cross-section area a m2 while the ram piston has a cross-section area Am2. When the plunger moves down a distance d, the ram piston moves up a distance d. i State the property of liquid on which the working of the hydraulic press works 1mark ii Derive an expression for the velocity ratio V.R in terms of A and a 3marks c A machine of velocity ratio 45, overcome a load of 4.5 103N, When an effort of 135N is applied. Determine i The efficiency of the machine 3marks ii The percentage of work that goes to waste 1mark www.freekcsepastpapers.com226 14. A Define specific latent heat of fusion of a substance 1mark b Water of mass 200g at a temperature of 60oC is put in a well lagged copper calorimeter of mass 80g. A piece of ice at 0oC and mass 20g is placed in the calorimeter and the mixture stirred gently until all the ice melts. The final temperature T of the mixture is then recorded. Take; specific latent of fusion of ice 334000J kg, s.h.c of water 4200j kg 1k 1, s.h.c of copper 900J kg 1k 1 Determine: i The heat absorbed by the melting ice at 0oC 1mark ii The heat absorbed by the melted ice water to rise to temperature T. answer may be given in terms of T 2marks iii The heat lost by the warm water and the colorimeter answer may be given in terms of T 2marks iv The final temperature of the mixture 3marks 15. A State Newton s second law of motion 1mark b A matatu starts from rest and accelerates to cover a distance of 49m in 7seconds. Determine its acceleration. 2mks c A trolley moving on a horizontal bench of height 1.2m strikes a barrier at the edge of the bench.


The figure below shows a ray of light incident on a glass prism. Given that the critical angle of the glass is 390, sketch on the diagram the path of ray through the prism until it exits the prism 2mks 6. A sharp point of a pin is held over a positively charged electroscope. State and explain the observation made on the electroscope 2mks www.freekcsepastpapers.com229 7. The figure below is a circuit of 3 resistors connected to a 12v battery. Determine the P.d across the 3 resistor 3mks 8. The figure below shows a magnet. Point A and B are in front of the magnet. On the axis provided sketch a graph showing how the magnetic field strength changes the A to B 2mks 9. The figure below shows a beam of beta particles entering a magnetic field whose direction below. Complete the diagram to show the path of the beta particles as they pass through magnetic field and out of it 1mk 10. A girl standing 400m from the foot of a high cliff claps her hand and the echo reaches her 2.32 seconds later. Calculate the velocity of sound in air using this observation. 2mks 11. Explain two of ways of dealing with defect of polarisation in a simple cell 2mks 12. The figure below shows an a.c source connected across diode D and Resistor R. Distance Magnetic field strength Magnetic fields Beam of beta particleswww.freekcsepastpapers.com230 On the axis provided sketch the output voltage as observed in the CRO 1mk SECTION B 55 MARKS 13. A The figure below shows a system of capacitor connected to a 100v d.c supply. From this circuit determine: i Its effective capacitance 2mks ii The charge through the F 6capacitor 2mks iii The p.d across F 8capacitor 2mks b State any two factors that affects the capacitance of a parallel plate capacitor 2mks 14.


Distance Magnetic field strength Magnetic fields Beam of beta particleswww.freekcsepastpapers.com230 On the axis provided sketch the output voltage as observed in the CRO 1mk SECTION B 55 MARKS 13. A The figure below shows a system of capacitor connected to a 100v d.c supply. From this circuit determine: i Its effective capacitance 2mks ii The charge through the F 6capacitor 2mks iii The p.d across F 8capacitor 2mks b State any two factors that affects the capacitance of a parallel plate capacitor 2mks 14. A The figure below shows the features of an x-ray tube i Name the parts labelled A and B 2mks ii Explain the effect of increasing the potential P on x-rays produced 2mks iii During the operation of the tube, the target become very hot. Explain how this heat is caused 2mks b In a certain x-ray tube, the electrons are accelerated by a p.d of 12kv. Assuming that all energy goes to produce x-rays, determine the frequency of x-ray produced h 6.62 10-34Js and e- 1.6 10-19C 3mks Time s Pd V www.freekcsepastpapers.com231 15. The figure below shows a connection to a 3-pin plug as viewed from its back i Name the terminal pin labelled A 1mk ii State any two mistakes with wiring of his 3pin plug 2mks iii Give any two reasons why the earth pin is normally longer than the other two pins 2mks b The figure below is graph of K.E of electrons against frequency of radiation in photo electric effect in cathode metal plate From the graph, determine i Threshold wavelength of the cathode metal surface 2mks ii Planck s constant h of cathode 2mks iii Work function of cathode in ev 2mks 16.


Explain how this heat is caused 2mks b In a certain x-ray tube, the electrons are accelerated by a p.d of 12kv. Assuming that all energy goes to produce x-rays, determine the frequency of x-ray produced h 6.62 10-34Js and e- 1.6 10-19C 3mks Time s Pd V www.freekcsepastpapers.com231 15. The figure below shows a connection to a 3-pin plug as viewed from its back i Name the terminal pin labelled A 1mk ii State any two mistakes with wiring of his 3pin plug 2mks iii Give any two reasons why the earth pin is normally longer than the other two pins 2mks b The figure below is graph of K.E of electrons against frequency of radiation in photo electric effect in cathode metal plate From the graph, determine i Threshold wavelength of the cathode metal surface 2mks ii Planck s constant h of cathode 2mks iii Work function of cathode in ev 2mks 16. A The figure below shows a simple cathode ray tube i Explain how the electrons are produced in the tube 2mks ii State one function of the anode 1mk www.freekcsepastpapers.com232 iii At what part of the cathode tube would the time base be connected? 1mk b The figure below represents a displacement time graph for a wave moving with a velocity of 80cm s Determine the wave i Frequency f 2mks ii Wavelength 2mks c A ray of light traveling through air in to medium 1 and 2 as shown in the figure below. I Calculate the refractive index of medium 1 1mk ii Angle of refraction r2 in medium 2 2mks 17. A State the Lenz s law of electromagnetic induction. 1mk b A bar magnet is moved into a coil of insulated copper wires connected to a centre zero galvanometer G as shown in the figure below.


I Calculate the refractive index of medium 1 1mk ii Angle of refraction r2 in medium 2 2mks 17. A State the Lenz s law of electromagnetic induction. 1mk b A bar magnet is moved into a coil of insulated copper wires connected to a centre zero galvanometer G as shown in the figure below. I With arrows show the direction of induced current in the coil 1mk ii Explain clearly what is observed on the galvanometer when the south pole of a magnet is moved into the coil and then withdrawn 2mks c A transformer has 1600 turns in the primary coil and 80 turns in the secondary coil. If the transformer is 80 efficient and its primary coil is 240v with a current of 0.75A, determine i The secondary e.m.f of its coil 2mks ii The output power in its secondary coil 2mks www.freekcsepastpapers.com233 18. A Define the term radioactivity 1mk b The figure below shows tracks formed in a diffusion cloud chamber given by a certain radioactivity sample State the type of radiations emitted by this sample, explain your answer 2mks c i The figure below shows radioactive decay of iodine. Ii What fraction of this iodine will have decayed after 3 half lifes 2mks d The average count rate of a radioactive material sample is 92 counts per second. After 420 seconds, the count rate had dropped to 29 counts per second. Given that the background count rate was 20 counts per second, determine the half-life of this sample. 3mks www.freekcsepastpapers.com224 CEKENA MOCK EXAMINATIONS, 2023 Kenya Certificate of Secondary Education K.C.S.E 232 3 PHYSICS Paper 3 CONFIDENTIAL 1. -. Two biconcave lenses 1st and 2nd f 10cm - Two lens holder - A white screen, I with cross wire - A white screen, II without cross wire - A meter rule - A plane mirror with surface area of the lens - A piece of cellotape - A lit candle source of light 2.


Given that the background count rate was 20 counts per second, determine the half-life of this sample. 3mks www.freekcsepastpapers.com224 CEKENA MOCK EXAMINATIONS, 2023 Kenya Certificate of Secondary Education K.C.S.E 232 3 PHYSICS Paper 3 CONFIDENTIAL 1. -. Two biconcave lenses 1st and 2nd f 10cm - Two lens holder - A white screen, I with cross wire - A white screen, II without cross wire - A meter rule - A plane mirror with surface area of the lens - A piece of cellotape - A lit candle source of light 2. A Voltmeter Ammeter 0 -1 A Switch 2 dry cells Cell holder Resistor R 10 Nichrome wire 0.3 0.02mm 7 connecting wire Micrometer screw gauge to be shared B Measuring cylinder at least 40cm Glycerine to fill the cylinder to 37cm Two rubber bands Tissue paper One ball bearing diameter 6mm 1 A magnet any permanent magnet A micrometer screw gauge A stop watch digital www.freekcsepastpapers.com225 CEKENA MOCK EXAMINATIONS, 2023 Kenya Certificate of Secondary Education K.C.S.E 231 3 PHYSICS PAPER 3 PRACTICAL TIME: 2 hours a Answer all questions b You are supposed to spend the first 15 minutes of the 2 hours allowed for this paper reading the whole paper carefully before commencing your work. C Marks are given for clear record of the observation made, their suitability accuracy and the use made of them. D Candidates are advised to record their observation as soon as they are made. E Non-programmable silent calculators and mathematical tables may be used. 1 You are provided with the following: a Two biconcave lenses, b Two lens holders c Lit candle d White screen, I with cross-wire e White screen II f A meter rule g A plane mirror h Cellotape Procedure i Mount 1st lens in the lens holder. Fix the plane mirror at the back of the lens using cellotape ii Arrange the setup as shown in figure below.


1 mark 3. Figure 2 shows some air trapped by mercury in a glass tube. The tube is inverted in a dish containing mercury. Given that the atmospheric pressure is 760 mmHg and the height of mercury column in the tube is 600 mm, determine the pressure of the air trapped in the tube in mmHg. 2 marks 4. Figure 3 shows drops of mercury and water on two glass beakers, Explain the difference in the shapes of the drops. 2marks Mercury droplet Water droplet 5. A ball is thrown from the top of a cliff 20m high with a horizontal velocity of 10ms-1. Calculate the distance from the foot of the cliff to where the ball strikes the ground. 3 marks b a Inside jaws Vernier scale Object Outside jaws Main scale Stripwww.freekcsepastpapers.comPage 209 6. Explain why a clinical thermometer is not sterilized using boiling water. 1mark 7. A boy blows through the mouth of a hollow vuvuzela as shown below. A light cork is suspended freely by a string as shown. Giving reason indicate the path taken by the cork 2 marks 8. A stopwatch reads 08:10:84 and 09:10: 90 before and after an experiment respectively. Determine the duration of the event in SI units. 2marks 9. Explain the meaning of thermodynamics as a branch of physics. 1 mark 10. A metal ball suspended vertically with a light string of length 4m is displaced through an angle as shown in the diagram below. The body is released from A and swings past the lowest point B. Given that its velocity at point B is 4 m s, determine angle 3 marks 11. Figure 5 shows a rectangular loop with a thin thread loosely tied and dipped into a soap solution. Draw on the space provided what is observed when point A is punctured. 1mark 12. Two horizontal strings are attached to a block, resting on a frictionless surface, as shown in figure 6. A force of 100N pulls on one string. The block does not move. Find the value of the force, F on the other string. 1 mark 13. A wooden bench feels neither warm nor cold when touched by your bare hands. Explain this observation.


Determine the temperature of the gas when the pressure increases to 900mmHg and the volume decreases to 15 cm3. 3 marks 18. A Define the term velocity ratio of a machine 1 mark b The figure 11, below shows part of the hydraulic lift system. State any one property of the liquid under which the hydraulic system works 1 mark c The hydraulic lift machine above has velocity ratio 45 and it overcomes a load of 4500 N when an effort of 135 N is applied. Determine: i The mechanical advantage of the machine 2 marks ii Efficiency of the machine 3 marks iii The percentage of work that goes to waste 1 mark www.freekcsepastpapers.comPage 212 KAKAMEGA FORM IV JOINT EXAMINATION, 2023 Kenya Certificate of Secondary Education 232 2 PHYSICS PAPER 2 Time 2 hours INSTRUCTIONS TO CANDIDATES. Answer ALL the questions. ALL working must be clearly shown. Non-programmable silent electronic calculators and KNEC mathematical table may be used SECTION A 25 MKS 1. State two differences between images formed by a plane mirror and a pinhole camera. 2mks 2. You are provided with connecting wires, 2 dry cells, a switch and two bulbs. Draw a circuit diagram to show; cells in parallel and controlled by one switch. 2mks 3. When an ebonite rod is rubbed using dry cloth it acquires negative charge. Explain how the negative charge is acquired 1mk 4. The diagram below shows a soft iron bar placed when poles of a magnet. Draw the magnetic field pattern produced. 2mks 5. The diagram below shows a conductor in a magnetic field Indicate on the diagram the direction of motion 1mk 6. State two applications of total internal reflection 2mks 7. You are provided with resistors 3.052, 4.052 and 6.052. Draw a circuit diagram to show how the three resistors can be connected together to give an effective resistance of 652. 2mks 8. The diagram below shows plane waves moving from shallow to deep end of a pond.


Draw a circuit diagram to show how the three resistors can be connected together to give an effective resistance of 652. 2mks 8. The diagram below shows plane waves moving from shallow to deep end of a pond. Shallow water Deep water a Complete the diagram to show the waves on the deep end 1mk b State what happens at the boundary to i The frequency of the waves 1mk ii The speed of the waves 1mk www.freekcsepastpapers.comPage 213 9. The figure below shows a simple cell. A When switch K is closed, the bulb lights brightly initially, but grow dim and dimmer until it goes off; i State the possible cause of this behaviour. 1mk ii State the remedy for the behaviour 1mk 10. The diagram below shows a wave profile Determine the frequency of the wave 3mks 11. State two ways of increasing the capacitance of a parallel plate capacitor 2mks 12. A driver was given tow mirrors-a plane mirror to choose from. He chose convex mirror as his driving mirror. Give two reasons why? 2mks SECTION B 55 MKS 13. A State Snell s law of refraction 1mk b In an experiment to determine the refractive index of a liquid, the liquid was poured into a measuring cylinder, a pin was placed at the bottom of the cylinder and another pin used to locate the apparent position of the first pin. The values of real and apparent depth were used to plot a graph as shown below. Real depth cm Apparent depth cm www.freekcsepastpapers.comPage 214 i From the graph determine the refractive index of the liquid 3mks ii Given that the velocity of light in vacuum is 30x 108m s, what would be the velocity of light in the liquid above?


A State Snell s law of refraction 1mk b In an experiment to determine the refractive index of a liquid, the liquid was poured into a measuring cylinder, a pin was placed at the bottom of the cylinder and another pin used to locate the apparent position of the first pin. The values of real and apparent depth were used to plot a graph as shown below. Real depth cm Apparent depth cm www.freekcsepastpapers.comPage 214 i From the graph determine the refractive index of the liquid 3mks ii Given that the velocity of light in vacuum is 30x 108m s, what would be the velocity of light in the liquid above? 2mks c The diagram below shows a ray of light incident on a glass-air interface Given that the refractive index of glass is 1.4, determine the value of 3mks d State two condition necessary for internal reflection to occur 2mks e The diagram below shows a ray of light incident at glass prism ABC at 90o Complete the ray to show how it emerges from the prism given the critical angle of the glass is 42o 14. A What is meant by the term capacitance? 1mk b The figure below shows a point placed near a positively charged rod. Draw on the diagram the resulting electric field patterns c When a positively charged conductor is brought close to a candle, the flame is diverted as shown in the figure below. Explain this observation 2mks www.freekcsepastpapers.comPage 215 d The figure below shows three capacitors of capacitance 3 F, 2MF and 6 F connected to a 12V supply circuit. Calculate: i The total capacitance of the circuit 3mks ii The total stored in the circuit 3mks iii The potential differences across 2 F capacitor 2mks 15. A Define principal focus of a biconcave lens 1mk b The diagram below shows a virtual image of an object placed in front of a biconvex lens. Draw appropriate rays to locate the object. C A convex lens forms a real image five times the size of the object on a screen.


A Define principal focus of a biconcave lens 1mk b The diagram below shows a virtual image of an object placed in front of a biconvex lens. Draw appropriate rays to locate the object. C A convex lens forms a real image five times the size of the object on a screen. If the distance between the object and the screen is 120Cm, determine; i image distance 2mk ii Focal length of the lens 2mks d The diagram below shows a defect in human eye. I Name the defect 1mk ii State two causes of the defect 2mks 16. A figure below shows how a student set up and circuit using three identical bulbs x, y and z each rated 12V, 2.0A www.freekcsepastpapers.comPage 216 i When operating normally, calculate the resistance of one of the bulbs 2mks ii Calculate the effective resistance of the three bulbs 2mks iii What will be reading of the ammeter? 2mks iv Draw a circuit diagram showing the three bulbs connected in such a way that they would all work at the same brightness especially if they are not identical 2mks b When the switch S is kept open in the circuit shown below the voltmeter reads 1.5V. When the switch is closed, the reading drops to 1.3V and the current through the resistor is 0.5A. i What is the e.m.f of the cell? 1mk ii What is the terminal voltage of the cell 1mk iii Calculate the value of R 2mks 17. In the experiment to observe interference of light waves a double slit is place close to the source of monochromatic light as shown below.


I What is the e.m.f of the cell? 1mk ii What is the terminal voltage of the cell 1mk iii Calculate the value of R 2mks 17. In the experiment to observe interference of light waves a double slit is place close to the source of monochromatic light as shown below. A i State the function of the double slit 1mk ii State and explain what is observed on the screen 3mks b State what is observed on the screen when: i The slit separation S1S2 is reduce 1mk ii White light source is used in place of monochromatic source 1mk c Distinguish between stationary waves and progressive waves in terms of their Propagation 1mk www.freekcsepastpapers.comPage 217 KAKAMEGA FORM IV JOINT EXAMINATION, 2023 Kenya Certificate of Secondary Education 232 3 PHYSICS Paper 3 PRACTICAL 2 hours INSTRUCTIONS Answer all questions. You are supposed to spend the first 15 minutes of the 2 hours allowed for this paper reading the whole paper carefully. Marks are given for a clear record of the observation actually made, their suitability, accuracy and the use made of them. Candidates are advised to record their observations as soon as they are made. Mathematical tables, slide rules and calculators may be used. Take 3.14 and gravitational acceleration g 10m s2 Question 1 You are provided with the following: - An ammeter - A voltmeter - A switch - A cell holder and two dry cells. -. A wire mounted on a mm labeled AB. -. Six connecting wires, at least three with crocodile clips. A Set up the apparatus as shown in the circuit diagram below in figure 2. Figure 2 Close the switch, using the voltmeter and ammeter measure the voltage and current when the distance L is approximately 100cm.


1 mark ii Measure and record the distance x between the two lenses and the distance y between the concave lens and the screen. 2 marks x . Y . I Find the focal length f of the diverging lens using the relationship, 3 marks www.freekcsepastpapers.comPage 220 KAKAMEGA FORM IV JOINT EXAMINATION, 2023 Kenya Certificate of Secondary Education 232 3 PHYSICS Paper 3 PRACTICAL CONFIDENTIAL Question 1 You are provided with the following: - An ammeter 0 1A - A voltmeter 0 3V - A switch - A cell holder and two dry cells. -. A nichrome wire swg 28 diameter 0.37mm mounted on a mm labeled AB to a length of 1m. - Six connecting wires, at least three with crocodile clips. Question 2 Each student to be provided with the following; Spring balance 100g mass labeled Solid A Water in a 100ml beaker About 100ml of glycerin in a 100ml beaker labeled Liquid L. Sewing thread about 20 cm Piece of tissue paper A convex lens of focal length 15cm and a lens holder A concave lens of focal length 15 and a lens holder A screen A meter rule A cross wire object A lit candlewww.freekcsepastpapers.comPage 191 MUMIAS WEST JOINT EVALUATION, 2023 Kenya Certificate of Secondary Education 232 1 Physics Paper 1 Time: 2hours Instructions to the candidates; Answer ALL the questions in sections A and B ALL working MUST be clearly shown. KNEC Mathematical tables and Non-programmable electronic calculators may be used. Take; g 10N kg SECTION A 25 MARKS 1. State two precautions to be observed when using a micrometer screw gauge. 2marks 2. The formula for determining weight of an object is given by w mg. Give the physical quantity represented by the letter g and state its S.I unit. 2marks 3. Figure 1 shows water in a tank.


Give the physical quantity represented by the letter g and state its S.I unit. 2marks 3. Figure 1 shows water in a tank. Determine the pressure exerted on the ground due the weight of the water. 3marks Take density of water to be 1000 kgm-3 4. A part from size of molecule, State two other factor that affect the rate of diffusion of a gas. 2marks 5. Figure 2 shows electric cables for power transmission. Explain why they are not fixed tightly. 2marks 6. A half-filled thermos flask is less likely to keep a liquid hot for a longer time than one which is completely filled. Explain. 2marks 7. A Define the moment of a force and state the S.I unit. 2marks b A uniform metre rule is balanced at the 30 cm mark when a load of 0.8N is hung at the zero mark as shown in figure 3 below. Fig 3 Determine the weight of the metre rule. 2marks 8. Figure 4 shows ice in a beaker. Fig.4 State and explain the effect of raising temperature on the overal stability of the beaker and its contents. 2marks 0.8N 10 20 30 40 50 60 70 80 90 0 100 Waterwww.freekcsepastpapers.comPage 192 9. The pointer of an unloaded spring reads 20 cm. When a mass of 120g is applied to the spring, the pointer reads 28cm. A pan in which a mass of 200g is placed is now hang from the spring and the pointer reads 35cm. Determine the mass of the pan. 3marks 10. Sketch a displacement-time graph for a body thrown upwards and falls back to the ground. 2marks 11. State one property of a fluid that obeys Bernoulli s effect. 1mark SECTION B 55 MARKS 12. A Show that, for an inclined plane, its velocity ratio is given by, 1 where is the angle of inclination. 3marks b Sketch a block and tuckle system of pullies with a velocity ratio of 4.


1mark SECTION B 55 MARKS 12. A Show that, for an inclined plane, its velocity ratio is given by, 1 where is the angle of inclination. 3marks b Sketch a block and tuckle system of pullies with a velocity ratio of 4. 3marks c Figure 5 shows a cross-section of a handle of a screw jack 70 cm long and pitch of the screw is 0.8 cm. Given that the efficiency is 60 , determine: i The velocity ratio of the system. 2marks ii If an effort of 50N is applied calculate the load that can be lifted. 3marks 13. A Define specific heat capacity and state its S.I unit. 2marks b Equal masses of water and paraffin are heated for same length of time. The final temperature of paraffin was found to be greater than the final temperature of water. Explain the observation. 2marks c A hot-water tank for a house contains 150kg of water at 150C. the tank itself has a heat capacity of 6000 JK-1. An immersion heater is used to heat the water to 500c. The tank is well insulated and the power of the heater is 2500W specific heat capacity of water 4200 JKg-1K-1 i Find the amount of heat transferred to the water 2marks ii Find how much heat is absorbed by the tank 2marks iii Determine the time it will take the heater to raise temperature to 500C. 3marks 14. A Explain the meaning of an ideal gas. 1mark b Sketch a graph of volume against the inverse of pressure at a constant temperature. 2marks c On the same axis of the sketch in 14 b above, sketch the graph when temperature is raised for the same gas 1mark d A bubble of air of volume 1cm3 is released by a deep-sea diver at a depth where the pressure is 30 atmospheres. Assuming its temperature remains constant. Determine its volume just before it reaches the surface where the pressure is 1.5 atmosphere? 3marks e Figure 6 shows apparatus used in investigating a gas law.


Assuming its temperature remains constant. Determine its volume just before it reaches the surface where the pressure is 1.5 atmosphere? 3marks e Figure 6 shows apparatus used in investigating a gas law. Study it and answer the questions that follow. I State the law under investigation. 1mark ii Describe how the set up can be used to verify the law stated in i above. 4marks 0.8cm 70 cm Handle Load Basewww.freekcsepastpapers.comPage 193 15. A Define the radian as applied in circular motion. 1marks b A body in circular motion with constant speed is said to be accelerating. Explain this observation. 1mark c Figure below shows masses A, B and C placed at different points on a rotating table. The angular velocity of the table can be varied. I State two factors that determine whether a particular mass slides off the table or not. 2marks ii State the mass that slides off last. Give a reason for your answer. 2marks iii A ball of mass 100g tied to a light to a light string is being whirled in a vertical circle of radius 0.5m with uniform speed. At the lowest position the tension in the string is 2.8N. Calculate i The angular velocity of the ball. 3marks ii The tension in the string when the ball is at the upper most position of the circular path. 2marks 16. A State two factors affecting the upthrust experienced by an object immersed in a fluid. 2marks b Explain how a submarine is made to float and sink in water. 2mark c Figure 8 shows a simple hydrometer. I Explain why the bulb is made wide. 2mark ii State the purpose of the lead shots in the glass bulb 1mark iii Describe how the hydrometer can be made more sensitive. 1mark iv Describe how the hydrometer is calibrated to measure relative density.


I Explain why the bulb is made wide. 2mark ii State the purpose of the lead shots in the glass bulb 1mark iii Describe how the hydrometer can be made more sensitive. 1mark iv Describe how the hydrometer is calibrated to measure relative density. 2marks Masses Rotating table B A Cwww.freekcsepastpapers.comPage 194 MUMIAS WEST JOINT EVALUATION, 2023 Kenya Certificate of Secondary Education 232 2 PHYSICS PAPER 2 THEORY TIME: 2 HOURS INSTRUCTIONS TO CANDIDATES: Answer all questions in section A and B. All working must be clearly shown. Scientific calculators and KNEC Mathematical tables may be used. Take g 10m s2 SECTION A 25 MARKS 1. The figure 1 below shows the image in front of a mirror M. By ray diagram construction, locate the position of the object. 2mks 2. Figure 2 below shows a sharp pin fixed on a cap of leaf electroscope. The electroscope is highly charged and then left for some time. Explain why the leaf collapses. 1mk 3. Explain how polarization reduces current in a simple primary cell. State how it can be reduced. 2mks 4. Fig 3 below shows a ray incident on a converging lens. Fig. 3 Complete the ray diagram by showing the emergent ray. 1mk 5. The chart below shows an arrangement of different parts of the electromagnetic spectrum. Radio A Infrared Visible B X-Rays Gamma Rays i Name the radiation represented by B. 1mk ii Name a device that can be used to detect radiation A. 1mk 6. An object is placed in between two parallel mirrors. How many images can a student see? 2mks Sharp pin Eye IConverging lenswww.freekcsepastpapers.comPage 195 7. A car battery requires topping up with distilled water occasionally. Explain why this is necessary and why distilled water is used 2mks 8. What causes electrical resistance in conductors? 1mk 9. In determining the depth of an ocean, an echo sounder producing ultrasonic sound is used. Give one reason why this sound is preferred.


1mk 9. In determining the depth of an ocean, an echo sounder producing ultrasonic sound is used. Give one reason why this sound is preferred. 1 mk 10. State the conditions necessary for a wave incident on a slit to be diffracted. 2mks 11. Figure represents a long horizontal insulated wire XY connected in an electric circuit. The circle represents where a plotting compass is placed on the wire. I In the circle put an arrow to show the direction the N pole of the compass will deflect when switch k. is closed. 1mk ii Mention any two ways of reversing the direction captured in i above. 2mk 12. The diagram below shows a permanent magnet suspended by a spring. State with a reason the behavior of the magnet when the switch is closed. 2mks 13. A Define principal focus as used in curved surfaces. 1mk b An object OB is placed in front of a convex mirror as shown below drawn to scale. I Draw a ray diagram to show the position of the image formed. 3mks KAX Y B O F C Soft iron core y x S Spring N Swww.freekcsepastpapers.comPage 196 SECTION B 55 MARKS 14. A State the basic law of electrostatics. 1mks b Figure 3 shows a pear shaped conductor with positive charged on its surface. A proof plane is used to touch side B of the conductor and then the cap of an uncharged electroscope. This is then repeated with side A. i Give the observation made on the electroscope in each case. 2mks ii What conclusion is drawn from the observation in i above 1mk iii Draw on the diagram above the illustration of your conclusion in ii above. 1mk iv Name one application of such a conductor. 1mk c The figure below shows an arrangement which may be used to charge a capacitor of capacitance 5 0F and then to connect it to a capacitor of capacitance 20 F. i The switch S is first placed at position A, so that the capacitor C is connected to the 12V dc supply. Calculate the charge stored in the capacitor. 3mks ii The switch S is now changed to position B.


The ammeter reading and voltmeter reading are shown on the scales belowwww.freekcsepastpapers.comPage 198 i Record these two readings. 2mk ammeter reading ................................................................................... A voltmeter reading ................................................................................... V d Using the values above calculate i the resistance of R, 2mks ii find the total resistance of the circuit 2mks e Which two indicators guide one on when to recharge a lead acid accumulator? 2mks 17. A Some students wish to determine the focal length of a convex lens of thickness 0.6cm using an optical pin and a plane mirror. Figure 6 shows the experimental set up when there is no parallax between the pin and the image. Determine the focal length of the lens 2mks b An optician in Eldoret Hospital examined an eye of a patient and made the following observations: Eye too short and the focal length of the eye lens short i State the eye defect the patient could be having. 1mk ii Use a diagram to describe how the defect could be corrected. 2mks c The graph below shows the variation of 1 v and 1 u in an experiment to determine the focal length of a lens. Fig. 7 i Use the graph to determine the focal length 3mks ii What is the power of the lens used? 2mks d A converging lens forms an image which is three times the object. Determine the focal length of the lens if the distance between the object and the screen is 80cm. 3mks 18. A The figure below shows a ray of light PQ incident on air-water interface. The ray strikes the bottom surface at M instead of N The ray makes an angle of 40o at N and 54o at M with the horizontal i Determine; I. the angle of incidence. 1mk II. The angle of refraction. 1mk ii Calculate the refractive index of water.


D Tap the wire at L 20cm. Close the switch read and record in the time provided the milliammeter and voltmeter reading. E Repeat the procedure in c for other values of L, shown in the table below and complete the table. 8mks L cm L m V Volts I mA I Amps IVR 20 30 40 50 60 80www.freekcsepastpapers.comPage 201 f i Plot the graph of R Y-axis against L m . 5mks ii Determine the slope of the graph. 3mks iii Given that APLR were A is the cross-sectional area of the wire and P is a constant for the material of the wire, determine the value of the constant P. 3mks QUESTION 2 PART A You are provided with the following: 1. A white screen with crosswires 2. A Mounted lens 3. A White screen 4. A Candle 5. A Metre rule Proceed as follows: f Estimate the focal length of the lens by focusing the image of a distant object on the screen provided e.g. distant window. Fo cm 1mark g Arrange the apparatus as shown. With the object cross-wires illuminated using a candle flame placed at 15 , move the screen until a sharp magnified image of the object is formed on the screen. Measure and record the corresponding value of y in the table.


2 marks 2. The diagram below shows a section of a micrometer screw gauge. A State the smallest measurement that can be made by the micrometer screw gauge. 1 mark b The thimble of the micrometer screw gauge is rotated through 2 revolution in the clockwise direction in order to measure the diameter of a marble. State the diameter of the marble. 1 mark 3. The figure below shows two identical containers A and B containing hot water and ice block. State with reason which water cools faster assuming that the wire gauge absorbs negligible heat. 2 marks 4. A bus that carries goods in the under seats carrier is more stable than one that carries goods in the carrier at the top. Explain why this is so. 1 mark 5. A turntable of radius 16 cm is rotating at 960 revolution per minute. Determine the angular speed of the turntable. 2 marks 6. Sketch a velocity time graph for a body initially moving at a velocity u before a force F is applied to it for 5 seconds and there after the force F is withdrawn. 2 marks Ice block wrapped with wire gauze Floating ice block Hot water B Awww.freekcsepastpapers.comPage 171 7. The figure below shows a pith ball in a container. 2 marks State and explain what would happen if air is blown over the mouth of the container. 2 marks 8. The figure below shows a capillary tube placed in a trough of a mercury. Give a reason why the level of mercury in a capillary is lower than in the beaker. 1 mark 9. A cork enclosing steam in a boiler is held by the system below. If the area of the cork is 15 cm2 and a force of 500N is needed to keep the cork in place, determine the pressure of the steam in the boiler. 3 marks 10. In an experiment a crystal of potassium permanganate was placed in water as shown below. After sometime, it was observed that the water turned purple. Explain the observation. 1 mark 11. An aircraft 300m from the ground traveling horizontally at 400m s releases a parcel. Calculate the horizontal distance covered by the parcel from the point of release. Ignore air resistance 2 marks 12.


An aircraft 300m from the ground traveling horizontally at 400m s releases a parcel. Calculate the horizontal distance covered by the parcel from the point of release. Ignore air resistance 2 marks 12. A 20kw immersion water heater is used to heat 5.0 x 10-3 m3 of water from 230C to 1000C. Given that 30 of heat is lost to the surroundings, determine the time used in heating the water. 2 marks 13. When the flask is placed in iced water the level on water rose and then fell. Explain the observation. 1 mark Container Pith ball Bench Potassium permanganate Cork Water Waterwww.freekcsepastpapers.comPage 172 SECTION B. 55 MARKS 14. The graph curve below show the variation of force against extension cm of the spiral springs of the same material, same wire thickness length but of different diameters one large and the other small . Identify which graph A or B represents which spring. 2 marks 15. A State the principle of moments. 1 mark b A uniform metal strip is 3.0cm wides 0.6cm thick and 100cm long. The density of the metal is 2.7g cm3. I Determine the weight of the metal strip. 3 marks ii The strip is placed on a pivot and kept in equilibrium by forces as shown. Determine the value of F and R. 3 marks 16. The figure below shows an inclined plane, a trolley of mass 60kg being pulled up the slope by a force of 200N parallel to the slope. The trolley is moved from X to Y. Determine the, i Work output of the system. 2 marks ii Work input of the system. 2 marks iii The frictional force between the wheels of the trolleys and the inclined plane. 2 marks iv The efficiency of the system. 2 marks v The velocity ratio of the system. 2 marks EXTENSION CM FORCE N www.freekcsepastpapers.comPage 173 17.


What volume of the glass lies under the surface of mercury. 3 marks d A piece of sealing wax, weighs 3N in air and 0.22N when immersed in water, calculate the density of the wax. 3 marks e A balloon weighs 10N and has a gas capacity of 2m3. The gas in the balloon has a density of 0.1kg m3. If the density of air is 1.3kgm-3, calculate the resultant force of the balloon when it is floating in air. 3 marks 19. A Distinguish between speed and velocity. 1 mark b The figure below shows the motion of a ticker tape through a ticker timer whose frequency is 100Hz. Determine i Velocity at AB and PQ. 2 marks ii Constant acceleration of the tape. 2 marks c State Newton s second law of motion. 1 mark www.freekcsepastpapers.comPage 174 NAKURU FORM IV JOINT EVALUATION, 2023 Kenya Certificate of Secondary Education 232 2 PHYSICS PAPER 2 THEORY 2 HOURS INSTRUCTIONS TO CANDIDATES a Answer ALL the questions in Section A and B. b All working MUST be clearly shown c Non-programmable silent electronic calculators and KNEC Mathematical tables may be used for calculations SECTION A 25 MKS 1. A Figure 1 shows a ray of light incident on a plane mirror at point X. FIGURE 1 Complete the diagram indicating the angle of reflection. 2mks b State one characteristic of the image formed on plane mirror, 1mk 2. A Figure 2 shows a stationary charged rode X placed between two freely suspended charged rods, Y and Z. The charge on rod Z is indicated. Identify the type of charge on rods X and Y. 1mk b State one use of a charged gold leaf electroscope. 1mk 3. State the reason why current produced by a simple primary cell decreases rapidly when the cell is in use. 1mk 4. A State the reason why a freely suspended magnet always settles facing a particular direction. 1mk b Figure 3 shows poles of two bar magnets placed close to one another.


1mk 4. A State the reason why a freely suspended magnet always settles facing a particular direction. 1mk b Figure 3 shows poles of two bar magnets placed close to one another. Sketch the magnetic field pattern in the space between the poles. 1mk 5. Figure 4 shows the cross section of a conductor carrying some current and held between magnet field. Indicate using an arrow on the diagram the direction the conductor moves when released. 1mk 6. A What is meant by the term echo? 1mk FIGURE 3 FIGURE 4 Conductor FIGURE 2www.freekcsepastpapers.comPage 175 b Compare the speed of sound in air and in steel. 1mk c State one difference between stationary wave and progressive wave. 1mk 7. A State one difference sound waves and radio waves. 1mk b Figure 5 shows how displacement varies with distance of a certain wave. 1mk FIGURE 5 On the same diagram, indicate the wavelength of the wave using the symbol. 1mk 8. A State one characteristic of images formed by a concave mirror. 1mk b Figure 6 shows a concave mirror of focal length 10cm and an object O, placed 15cm in front of the mirror. Using a ray diagram, complete the diagram to locate the image, I, formed. 2mks 9. Figure 7 shows an immersion heater used to heat some water initially at 250C to boiling point. State two factors that determine the time taken for the water to boil. 2mks 10. A radioactive substance initially has a mass of 0.4g and decays to 0.05g in 75 minutes. Determine the half-life of the substance. 2mks 11. State one difference between X-rays and infrared waves. 1mk 12. Figure 8 a and b shows P n junctions, each connected to a cell and a lamp. It is observed that the bulb in a does not light while the bulb in b lights. Explain the reason for these observations.


Figure 8 a and b shows P n junctions, each connected to a cell and a lamp. It is observed that the bulb in a does not light while the bulb in b lights. Explain the reason for these observations. 2mks Displacement cm Water Heating coil Distance cm www.freekcsepastpapers.comPage 176 SECTION B 55 MARKS 13. A Define the term critical angle of a refracting media. 1mk b One of the conditions necessary for total internal reflection to occur is that the critical angle must be exceeded. State the other condition. 1mk c The figure below shows a ray of light travelling from air and through a prism made of glass of refractive index 1.7. I On the diagram show the critical angle. 1mk ii Determine the I Critical angle 2mks II. Angle x and y 2mks 14. A Define the term Thermionic emission 1mk b The figure below shows the sketch of a cathode ray Oscilloscope. I Label the parts marked A and C. 2mks ii State the functions of the parts labeled B and D. 2mks iii Explain briefly how the C.R.T works. 2mks 15. When a radiation of wavelength 1.8 x 10-9 m falls on a photo emissive surface, the photoelectrons can be stopped when a positive terminal of 400V is applied on the surface. Given that the electronic charge 1.6 x 10-19 C, mass of the electron 9.1 x 10-31 kg, Planck s constant 6.62 x 10-34 Js, C 3.0 x 108m s, calculate the; i The work function of the surface. 2mks ii The threshold frequency. 2mks 16. The figure below shows a 3- pin plug with the wires connected. A i Identify the pins A, B and C and give the colour code of each. 3mks ii State the pin to which a switch should be connected to.


Determine the i Maximum energy contained in the cathode electrons. 1mk ii Wavelength of the x-rays produced. 2mks Take h 6.62 x 10 -34Js, C 3.0 x 108 m s 19. The figure below shows two capacitor plates held parallel to each other. A State and explain what happens to the capacitance of the plates if the top plate is moved as shown. 2mks b Show that if three capacitors in parallel have capacitances C1, C2 and C3, then the network capacitance is given as follows. CN C1 C2 C3 2mks c The figure below shows a network of capacitors. Determine the network capacitance. 2mks 20. A The figure below shows an experimental set-up consisting of a mounted lens L, a screen S, a metre rule and a candle. I Describe how the set-up may be used to determine the focal length, f, of the lens. 4mks ii State the reason why the set-up would not work if the lens was replaced with a diverging lens. 1mk b An object placed 15cm from a convex lens is magnified two times. Determine the focal length of the lens. 3mks Candle 10 F 5 F 1 F 7 F 3 F 2 F L S Metre rulewww.freekcsepastpapers.comPage 179 NAKURU FORM IV JOINT EVALUATION, 2023 Kenya Certificate of Secondary Education 232 3 PHYSICS Practical PAPER 3 CONFIDENTIAL Question 1 A 100 cm nichrome wire mounted on a millimeter A B S.W.G 28. An ammeter 0 1A . A voltmeter 0 5 V . 2 dry cells 1.5V each . A cell holder. A torch bulb and a bulb holder. Eight connecting wires at least 4 with crocodile clips. A switch. A micrometer screw gauge. Question 2.


D1 d2 1mk Average of d1 and d2 mm 1mk b Connect the apparatus as shown below. Fig 1 c Place the sliding contact at P 20cm from A and then close the switch. Record the readings of both the current and voltage in the table below. D Repeat the above experiment by placing P at 40cm, 60cm, 70cm, 80cm and 100cm from A. Record your readings in the table below. 5 mks i Length cm Ammeter reading I A Voltmeter reading P.d V 20 40 60 70 80 100 A Bwww.freekcsepastpapers.comPage 181 ii What happens to the bulb as L increases? 1mk e i Plot a graph of I A against P.d V on the grid provided. 5mks ii Determine the slope of the graph at V 0.6V, stating its SI units. 3mks iii Determine the cross section area A of the wire in m2. 2mks iv Given that AeILV find e at L 0.70M. 2mks Question 2 Part A You are provided with the following: A coin 20 shilling coin Metre rule labeled with its mass Knife edge Measuring cylinder, 100ml Container with water Procedure i Record the mass of the rule Mr. Mr g 1mk ii Balance the rule on the knife edge. C.O.G cm 1mk iii Put the rule on the knife edge d1 cm from the centre of the rule. Iv Place the coin as shown in the figure below and adjust it until it gain balances horizontally. Fig 2. V Measure d1 cm 1 2mk d2 cm 1 2mk vi Determine mass of coin MC in grams. 2mks 1.3dd x MM21rC vii Using the measuring cylinder, estimate the volume of the coin.


Fig 2. V Measure d1 cm 1 2mk d2 cm 1 2mk vi Determine mass of coin MC in grams. 2mks 1.3dd x MM21rC vii Using the measuring cylinder, estimate the volume of the coin. VC cm3 1mk viii Calculate the density of the material of the coin. C g cm3 1mk PART B You are provided with the following a triangular glass prism a metre rule a 50 g mass some hot water some cold water some thread a thermometer one stand, one boss and clamp a beaker Proceed as follows a Using a piece of thread suspend the metre rule from the clamp on the stand and adjust the position of the thread until the metre rule balances horizontally. Note this position, O of the thread. This position of the thread must be maintained throughout the experiment www.freekcsepastpapers.comPage 182 b Using another piece of thread suspend the glass prism from the meter rule at a point 35cm from O. Suspend the 50g mass on the opposite side of O using another piece of thread. Adjust the position of the thread attached to the 50g mass until the metre rule balances once more. I Determine the distance L1 between O and the point of support of the 50g mass. L1 cm 1mk ii Use the principle of moments to determine the weight W1 of the prism in air. Take g 10N kg 2mks c. Put cold water into the beaker approximately three quarter full . With the glass prism still at 35cm from O, determine the distance L2 of the 50g mass at which the rule balances when the prism is fully submerged in the cold water. I L2 cm 1mk II Determine the weight W2 of the prism in the cold water. 2mks d Measure and record the temperature T1 of the cold water when the system is balanced.


With the glass prism still at 35cm from O, determine the distance L2 of the 50g mass at which the rule balances when the prism is fully submerged in the cold water. I L2 cm 1mk II Determine the weight W2 of the prism in the cold water. 2mks d Measure and record the temperature T1 of the cold water when the system is balanced. T1 0C 1mk e Now pour out the cold water and replace it with hot water. Balance the metre rule with the prism fully submerged in hot water. Ensure that the prism is still supported at 35cm from O. i Determine the distance L3 of the point of support of the 50g mass when the prism is submerged in hot water. L3 cm 1mk ii Measure and record the temperature T2 of the hot water. T2 0C 1mk iii Determine the weight W3 of the prism in hot water. 2mks f Determine the constant k for the water given that: 2mks 21TTWWWWWWk Prism Metre rule Stand Cold water Stand Metre rule Prism 50g L2 35cm 50g 35cm L1www.freekcsepastpapers.com 154 EASTERN CLUSTER EVALUATION, 2023 Kenya Certificate of Secondary Education KCSE 232 1 PHYSICS PAPER 1 TIME: 2 HOURS Instructions to candidates i Answer ALL the questions in section A and B. ii ALL working MUST be clearly shown. Iii Non programmable silent calculators may be used. SECTION A 25 MARKS Answer all the questions in this section. 1. A stopwatch reads 01:10:84 and 02:26:90 before and after an experiment respectively. Determine the duration of the event in SI units. 2 marks 2. Explain the meaning of thermodynamics as a branch of physics. 1 mark 3. Two glass tubes are dipped into a beaker of water as shown in figure 1 below: Indicate on the diagram, the level of water in the glass tubes 1 mark a Explain your answer in 3 a above 2 marks 4.


Explain the meaning of thermodynamics as a branch of physics. 1 mark 3. Two glass tubes are dipped into a beaker of water as shown in figure 1 below: Indicate on the diagram, the level of water in the glass tubes 1 mark a Explain your answer in 3 a above 2 marks 4. A body is vertically projected upwards from the ground at a velocity of 5m s and takes 1 seconds to return to the ground. Draw a velocity-time graph of the body for its entire duration of flight. 2 marks 5. Motor vehicles such as tractors which work on swampy areas have wide tyres fitted on them. Explain. 1 mark 6. The figure 2 below shows a uniform metre rule which is pivoted at 30.0cm mark. The spring balance is fastened at the 100cm mark and it is at equilibrium when the spring balance records 1.2N. Figure 2 Determine the weight of the metre rule. 3 marks 7. In the determination of size of an oil molecule, lycopodium powder is sprinkled on the water surface before oil drop is introduced onto the surface of the water. Give reason for this. 1 mark 8. In a hydraulic lift, a force, F1, is applied on the effort piston of cross sectional area, A1. A force F2, is experienced on the load piston of cross sectional area, A2 .applying the principle of transmission of pressure in liquids derive an expression for the force F2 in terms of F1, A1 and A2. 2 marks 9. Alcohol and mercury are the two most used thermometric liquids. Give a reason why one would prefer alcohol to mercury for a particular measurement of temperature 1 mark 0cm 3O cmSpring balance 100cmwww.freekcsepastpapers.com 155 10. The figure 3 below shows a funnel inverted over a light pith ball on a table. Air is blown into the funnel as indicated on the diagram. Give a reason why the pith ball rises. 2 marks 11. A trolley of mass 20kg moving at 0.8m s on frictionless horizontal surface was acted upon by a force of 2.5N. After impact the body moves at 4.8m s. Determine the time of impact of the force.


A trolley of mass 20kg moving at 0.8m s on frictionless horizontal surface was acted upon by a force of 2.5N. After impact the body moves at 4.8m s. Determine the time of impact of the force. 3 marks 12. The figure 4 below shows two identical thermometers A and B placed near and at equal distances on either side of a hot metal plate painted black on the side A and silvery on side B. Figure 44 State and explain the observation made on the reading of the thermometers after some minutes. 2 marks 13. The figure 5 below shows beaker containing water at 00. The beaker is placed on a bench. Figure 5 State and explain the changes in stability of beaker when water freezes. 2 marks SECTION B 55 Marks Answer all questions in this section. 14. A pulley system having a velocity of 3 is used to raise a load of 800N through a height of 0.6m at a constant speed using an effort of 300N in a time of 15 seconds. A Draw a diagram in the spaces provided below to show the pulley system and on it mark the direction of tension on all the string sections Label the load and effort 2marks b Calculate the mechanical advantage of the pulley system; 2marks c Find the efficiency of the pulley system; 3marks d Calculate the power developed by the effort. 3 marks e Give two reasons why the efficiency of the pulley system is less than 100 . 2 marks 15. A State two ways in which the centripetal force on a body of mass M can be increased. 2 marks b Figure 7 below shows an object of mass 200g at the end of a string 120cm long being whirled round a vertical circle in the direction shown. Figure 7 Air Pith ball Figure 3 RWater at 00C Rwww.freekcsepastpapers.com 156 i State two forces acting on the object at any instant as it continues to move in the vertical circle. 2 marks ii Indicate with an arrow on the figure the direction of the Centripetal force F and theVelocity V at the position of the object shown.


2 marks b Figure 7 below shows an object of mass 200g at the end of a string 120cm long being whirled round a vertical circle in the direction shown. Figure 7 Air Pith ball Figure 3 RWater at 00C Rwww.freekcsepastpapers.com 156 i State two forces acting on the object at any instant as it continues to move in the vertical circle. 2 marks ii Indicate with an arrow on the figure the direction of the Centripetal force F and theVelocity V at the position of the object shown. 2 mark iii State the reason why the object is accelerating while its speed remains constant. 1 mark iv Given that the angular velocity of the body is 5 rad s-1, find the: I. linear velocity 2 marks II. Tension of the string at point R, the lowest point. 3 marks 16. A State two differences between boiling and evaporation. 2mks b The figure 6 below shows two identical containers A and B containing hot water and ice block. State with reason which water cools faster assuming that the wire gauge absorbs negligible heat. 2mks c 1200 g of a liquid at 200C is poured into a well-lagged calorimeter. An electric heater rated 1 kW is used to heat the liquid. The graph below shows the variation of temperature of the liquid with time. Use the graph below to answer the following questions: i What is the boiling point of the liquid? 1 mark ii How much heat is given out by the heater to take the liquid to the boiling point? 2marks iii Determine the specific heat capacity of the liquid. 3marks iv If 50 g of the liquid vapour was collected by the end of the 10 minutes, determine the specific latent heat of vaporization of the liquid. 3 marks Ice block wrapped in wire gauze Hot Water Floating ice B Awww.freekcsepastpapers.com 157 17. A Sketch a graph of volume of a fixed mass of a gas against pressure on the axes below. 1 mark b Explain why an air bubble increase in volume as it rises from the bottom of a lake to the surface.


3 marks Ice block wrapped in wire gauze Hot Water Floating ice B Awww.freekcsepastpapers.com 157 17. A Sketch a graph of volume of a fixed mass of a gas against pressure on the axes below. 1 mark b Explain why an air bubble increase in volume as it rises from the bottom of a lake to the surface. 2 marks c When an inflated balloon is placed in a refrigerator it is noted that its volume reduces, use the kinetic theory of gases to explain this observation. 2marks e A glass capillary contains enclosed air by a thread of mercury 15cm long when the tube is horizontal, the length of the enclosed air column 24cm as shown. I What is the length of the enclosed air column when the tube is vertical with the open end uppermost if the atmosphere pressure is 750mmHg? 3 marks ii Explain why the mercury does not run out when the tube is vertical with the closed end uppermost. 1mark 18. A State Archimedes principle. 1mark b Figure below shows an experiment used to determine the density of an irregular piece of metal. The mass of metal in air is 200g. i Determine the volume of the stone in cubic metres. 2marks ii Calculate the density of the metal to 3 significant figures. 2marks c Given that the density of water is 1g cm3, determine; i The mass of water displaced. 2marks ii The up thrust acting on water. Take acceleration due to gravity, g, as 10ms2 2marks Volume V,Pressure P,24cm15cmwww.freekcsepastpapers.com 158 EASTERN CLUSTER EVALUATION, 2023 Kenya Certificate of Secondary Education 232 2 PHYSICS PAPER 2 THEORY TIME: 2 HOURS SECTION A 25 MKS 1. State the effect on the image on the pinhole camera when more holes are added to the first hole. 1mk 2. Explain why it is necessary to leave the caps of a lead acid accumulator open while charging. 1mk 3. A current carrying conductor AB is in a magnetic field as shown below. A Indicate on the diagram the direction of the force F acting on the conductor.


1mk 3. A current carrying conductor AB is in a magnetic field as shown below. A Indicate on the diagram the direction of the force F acting on the conductor. 1mk b State two factors that determine the direction of the force F. 2mks 4. A boy stands some distance from a high wall and claps his hands. What two measurements would need to be made in order to determine the speed of sound. 2mks 5. The depth of water in a pond is d1 cm. A point at the bottom of the pond appears raised by d2 cm when viewed from the surface. Determine the refractive index of water in terms of d1 and d2. 2mks 6. The figure below shows a displacement of a progressive water wave incident on a boundary between deep and shallow regions. I Complete the diagram to show what is observed after the boundary. 1mk ii What change occurs in the speed of the waves after the boundary? 1mk 7. An electric bulb is rated 75 W, 240v. Determine the resistance of the bulb. 3mks 8. The figure below shows a convex lens L an object O and a ray R passing through the lens and the possible path of the ray after passing through the lens. Complete the diagram and locate the position of the image I. 2mks 9. The chart below shows an arrangement of different parts of the electromagnetic spectrum. RADIOWAVES A INFRARED VISIBLE LIGHT B X-RAYS GAMMA RAYSwww.freekcsepastpapers.com 159 i Name the application of the radiation represented by B. 1mk ii Name a device that can be used to detect radiation A. 1mk 10. The figure below shows the main components of a cathode ray oscilloscope. I Name the part labelled A. 1mk ii What is the function of part labelled C. 1mk iii Explain how electrons are produced in a CRO. 1mk 11. The following reaction is part of a radioactive series. R 83210 --------- 84210 --------------- i Identify the radiation r. 1mk ii Determine the value of C.


The following reaction is part of a radioactive series. R 83210 --------- 84210 --------------- i Identify the radiation r. 1mk ii Determine the value of C. 1mk 12. Explain briefly the doping process involved in making n-type semiconductor. 2mks SECTION B: 55MKS 13. A State Ohm s law. 1mk b Differentiate between ohmic and non ohmic conductors. 1mk c A battery of 12 v and an internal resistance of 1 ohm is used in the circuit below. Determine: i The ammeter reading. 3mks ii The reading on a voltmeter placed across the terminals of the battery. 2mks iii The reading on the voltmeter placed across PQ. 3mks 14. A Define capacitance of a capacitor. 1mk b State the effect on the capacitance of increasing the distance of separation of a parallel plate capacitor 1mk c The circuit below shows a capacitor connected to a 12v battery. I Find the combined capacitance. 3mks ii Find the total charge stored in the circuit. 3mks iii Find the charge stored on the 2uf capacitor. 2mks iv Find the total energy stored. 3mks www.freekcsepastpapers.com 160 15. A State Faraday s law of electromagnetic induction. 1mk b The figure below shows a step-up transformer commonly used at a power station. I What is meant by a step-up transformer? 1mk ii Why does a transformer work with a.c only? 1mk iii What is the purpose of the laminated soft iron core? 1mk iv From the information, determine:- I Voltage in the primary circuit. 2mks II Voltage in the secondary circuit. 2mks c The figure below shows a coil being rotated in a clockwise direction in a magnetic field. The set up produces an alternating current. Initially the coil lies in the plane of the field as shown below. I Name the parts labelled A and B.


I What happens to the leaf of the electroscope? 1mk ii What would happen if radiation was red light? 1mk iii How is the cooling achieved in this kind of x ray machine? 3mks c In an experiment to find the relationship between frequency of a radiation and kinetic energy of the photoelectrons in a photoelectric device the following graph was obtained. Use the graph to determine i The Planck s constant h. 3mks ii The work function 2mks Zinc platewww.freekcsepastpapers.com 162 EASTERN CLUSTER EVALUATION, 2023 Kenya Certificate of Secondary Education 232 3 PHYSICS Paper 3 PRACTICAL CONFIDENTIAL Question One - Two dry cells of 1.5V each. -. Nichrome wire labeled W mounted on a metre rule. -. An ammeter 0-1.5A or 0-2.5A - A cell holder. -. Voltmeter. -. 8 connecting wires atleast 4 wash crocodile clips or a Jockey - A switch. -. A metre rule. Question Two - A metre rule. -. 10cm long cotton thread. -. Two masses of 10g. - Two masses of 20g. - Knife edge, 20cm high. -. A candle. -. A lens holder. -. A white screen. -. Converging len of focal length 15cm. Www.freekcsepastpapers.com 163 EASTERN CLUSTER EVALUATION, 2023 Kenya Certificate of Secondary Education KCSE 232 3 Physics Paper 3 PRACTICAL 2 Hours Answer all the questions. Question One You are provided with the following: - Two cells of 1.5V each - Nichrome wire labeled W mounted on a metre rule - An ammeter 0 1.5A or 0 - 2.5A - A cell holder - Voltmeter 0 5V - 8 connecting wires at least 4 with crocodile clips or a jockey - A switch - A metre rule Proceed as follows: a Connect the circuit as shown in the figure 1 below.


Adjust the knife edge until the metre rule balances again at new mark. Record the length d1 and the corresponding length d2. I Repeat the procedure for different masses and complete the table 2 shown below. Table 2 Mass, m g 10 20 30 40 50 60 Distance d1 cm Distance d2 cm Mass m x distance d2 md2 ii Plot a graph of md2 against d1 5mks iii Calculate the slopes of the graph 2mks Part B You are provided with the following apparatus - A lens - A lens holder - A candle - A white screen - A metre rule Procedure e Set up the apparatus as shown in the figure 3 below: f Starting with u 30cm adjust the position of the screen to obtain a sharp image of the candle. Record value of V in the table shown below: g i Repeat the procedure above for u 20cm and complete table below: 2mks Table 3 u cm v cm M 20 30 ii Given that the focal length of the lens satisfies the equation, 1 determine the average value of the focal length. Www.freekcsepastpapers.comPage 138 IGAMBA NG OMBE Kenya Certificate of Secondary Education K.C.S.E 232 1 PHYSICS Paper 1 Time: 2 Hours INSTRUCTION TO CANDIDATES Answer ALL Questions in sections A and B. ALL workings MUST be clearly shown Mathematical tables and electronic calculators may be used. SECTION A 25 MARKS Answer ALL questions in this section in the spaces provided 1. A student used the apparatus shown in figure 1 below to determine the diameter of a cylinder. Fig. 1 What is the diameter of the cylinder? 1mk 2. An old man warming himself next to a jiko receives heat mostly by radiation. Explain why. 2mks 3. A hole of area 200mm2 at the bottom of a tank 4.0m deep is closed with a cork. Determine the force due to water Density of water is 1000kg m3, and acceleration due to gravity is 10m s2 3mks 4.


2mks 3. A hole of area 200mm2 at the bottom of a tank 4.0m deep is closed with a cork. Determine the force due to water Density of water is 1000kg m3, and acceleration due to gravity is 10m s2 3mks 4. Give a reason why the scale of a hydrometer is calibrated downwards. 1mk 5. A fisherman jumping a shore from a boat may fall into water even if the boat is very close to the shore. Explain. 3mks 6. Explain why unboiled egg stops faster than a boiled egg when both are rolled together on a flat horizontal surface with same velocity. 2mks 7. An air bubble was released at the depth of 45m in a sea. The initial volume of the bubble at this depth was 3.0 x 10-5m3 and the temperature of water was 130C. What was its volume on reaching the surface of the water where the temperature was 230c. Atmospheric pressure 101Kpa and density of sea water 1020kgm-3 3mks 8. The diagram fig. 2 below shows a system of four pulleys. Show on the diagram how the string can be fixed so that the pulley has a velocity ratio of 3. 2mks 9. In the smoke cell experiment to show Brownian motion in gases, white specks in constant random motion are seen in the cell. What changes would be observed if the same set up is viewed at room temperature of about 250C and the then at a temperature of 140C. Explain your observation. 3mks 10. When two pieces of ice blocks are squeezed together once they form one block. Explain. 1mk 11. State two factors affecting centripetal force of a body moving in a circle. 2mks 12. Differentiate between streamline flow and turbulent flow. 1mk 13. Give one advantage of alcohol over mercury as a thermometric liquid. 1mk Fig. 2www.freekcsepastpapers.comPage 139 SECTION B 55 MARKS Answer ALL questions in this section. 14. The diagram fig.


2www.freekcsepastpapers.comPage 139 SECTION B 55 MARKS Answer ALL questions in this section. 14. The diagram fig. 3 below shows an arrangement that a certain student set up in a physics lab without the consent of the teacher. He allowed some volume of water into the glass tube and measured the corresponding height h of water in the tube using a ruler. He tabulated his data as below. Burette reading cm3 5.1 8.2 15.4 21.5 28.0 35.6 Height h, cm 3.8 5.8 10.5 14.5 18.7 23.2 a i Draw a graph of the burette reading against height h of the water in the glass tube. 5mks ii Use your graph above to determine the area of cross section of the glass tube. 3mks iii Use your graph to determine how far the zero mark of the ruler is from the end placed on the base of the stand. 2mks 15. A i State the law of floatation. 1mk ii Explain why a hollow metal sphere floats on water while a solid metal sphere of the same material sinks in water. 2mks b The diagram fig. 4 below shows a uniform block of uniform cross-sectional area of 6.0cm2 floating on two liquids A and B. The lengths of the block in each liquid are shown. Given that the density of liquid A is 800kg m3 and that of liquid B is 1000kgm-3 determine the: 16. The diagram fig. 5 below shows apparatus used to investigate how pressure of some trapped air varies with temperature. A Name the parts X and Y. 2mks b What are the functions of 2mks i The stirrer ii Part Y. c At what Kelvin temperature will the pressure of the air theoretically be zero? 1mk d What name is given to this temperature? 1mk e A certain mass of helium gas occupies a volume of 1.6m3 at a pressure of 1.5 x 105pa at 120C. Determine its volume when the temperature is 273k at 1.0x105pa.


I Show on the diagram the direction in which the stone flies when the string breaks and the position at which it breaks. 2mks ii Determine the speed at which the string breaks. 3mks c State one application of uniform circular motion. 1mk B A 3.3m 1.5m Fig. 6 C a i Determine the speed of the stone in ms 1 3mks ii Determine the tension in the string at positions B and C respectively. 4mks www.freekcsepastpapers.comPage 141 IGAMBA NG OMBE Kenya Certificate of Secondary Education K.C.S.E 232 2 PHYSICS Paper 2 Time: 2 Hours SECTION A 25 MARKS Answer all questions. 1. What property of light is illustrated by formation of shadows? 1mk 2. Other than local action state another defect of a simple cell and explain how it reduces the current produced. 2mks 3. The figure below shows a simple experiment using a permanent magnet and two metal bars X and Y. State, with reason, which bar is a soft magnetic material. 2mks 4. The figure below shows the image formed when an object is placed in front of a concave lens. Using suitable rays locate the position of the object. 3mks 5. Sketch the magnetic field pattern between the two poles of the magnet shown below. The wire carrying current is in between the poles. 2mks 6. The figure below shows a displacement time graph for a wave. Determine the frequency of the wave. 3mks 7. A mine worker stands between two vertical cliffs 500m from the nearest cliff. The cliffs are x metres apart. Every time he strikes the rocks, he hears the echos. The first one comes after 2.5s while the other comes 3s later. Calculate the distance between the cliffs. 3mks Metal bar Y Metal bar X During attraction After attraction X Ywww.freekcsepastpapers.comPage 143 14. A Define radioactivity. 1mk b Four nuclides are represented by the following symbols. 234 235 234 238 89 92 90 92 i Which nuclides are isotopes and which ones are isobars of the same element?


A Define radioactivity. 1mk b Four nuclides are represented by the following symbols. 234 235 234 238 89 92 90 92 i Which nuclides are isotopes and which ones are isobars of the same element? 2mks ii Name the nuclides one of which could be produced from the other by emission of a beta particle. Write the equation of the reaction 2mks iii A manufacturer wishes to check on the thickness of steel sheets he produces. Describe how this could be done using radioactive source and a counter. 3mks c Explain how N-type and P-type semi-conductors are obtained. 3mks d Sketch a graph below of voltage against time for full wave rectification using 4 diodes. 2mks 15. A Name any two electromagnetic waves whose wavelength is shorter than visible light. 2mks b i The diagram above shows part of x-ray tube. Name parts A and B 2mks ii Why is part B preferred 1mk c i State two differences between x-rays and cathode rays. 2mks ii What is the effect on the wavelength of x-rays if the number of electrons hitting metal target are increased. 1mk iii What is the effect on wavelength of x-rays when p.d across the tube is decreased? 1mk d Calculate the maximum velocity of electrons that would produce x-rays of frequency 8.0 x 108Hz if only 20 of kinetic energy is converted to x-rays. 3mks Take Planks constant 6.63 x 10-34JS e The circuit diagram below was used to light 3v 0.5A bulb from 12.0v d.c supply. Determine the rate at which electrical energy is converted into heat energy in appliance R.


1mk d Calculate the maximum velocity of electrons that would produce x-rays of frequency 8.0 x 108Hz if only 20 of kinetic energy is converted to x-rays. 3mks Take Planks constant 6.63 x 10-34JS e The circuit diagram below was used to light 3v 0.5A bulb from 12.0v d.c supply. Determine the rate at which electrical energy is converted into heat energy in appliance R. 3mks W X Y Z Voltage Time s A B X rayswww.freekcsepastpapers.comPage 144 IGAMBA NG OMBE Kenya Certificate of Secondary Education K.C.S.E 232 3 PHYSICS PAPER 3 CONFIDENTIAL QUESTION 1 PART A You are provided with the following; Metre rule Complete stand A spring with a pointer Three masses one 100g mass and two 50g mass Stop watch PART B A rubber bung Approximately: D 2.53cm, d 2.00cm, h 2.81cm Vernier caliper Beam balance QUESTION 2 You are provided with the following. An ammeter 0-3A A voltmeter 0-5V 2 Dry cells A resistance wire mounted on mm scale 6 connecting wires A torch bulb in a bulb holder A cell holder A switch A jockeywww.freekcsepastpapers.comPage 145 IGAMBA NG OMBE Kenya Certificate of Secondary Education K.C.S.E 232 3 PHYSICS PRACTICAL PAPER 3 TME: 2 Hours INSTRUCTIONS TO CANDIDATES a Answer all questions. B You are supposed to spend the first 15 minutes reading the whole paper carefully before commencing your work. C Candidates are advised to record their observations as soon as they are made. D Marks are given for observation actually made, their suitability, accuracy and the use made of them.


B You are supposed to spend the first 15 minutes reading the whole paper carefully before commencing your work. C Candidates are advised to record their observations as soon as they are made. D Marks are given for observation actually made, their suitability, accuracy and the use made of them. QUESTION 1 PART A You are provided with the following; Metre rule Complete stand A spring with a pointer Three masses one 100g mass and two 50g mass Stop watch Proceed as follows; a Set up the apparatus as shown; b Hang the unloaded spring and record the pointer readings. X0 . M 1 mk c i Load a mass of 150g and determines the extension of the spring e1 .. m 1mk ii Displace the 150g mass slightly downwards and release it to oscillate vertically. Time 20 oscillations and obtain t1. T1 s 1mk iii Find the periodic time T1. T1 s 1mk iv Use the equation T1 2 to find the value of P1 . 2mks d i Load a mass of 200g and determines the extension of the spring e2 m 1mk ii Displace the 200g mass slightly downwards and release it to oscillate vertically. Time 20 oscillations and obtain t2. T2 s 1mk iii Find the periodic time T2. T2 . S 1mk iv Use the equation T2 2 to find the value of P2 . 2mks e Find the average of p. 2mks pav 1 22 Pointer Metre lSpring Stand Mwww.freekcsepastpapers.comPage 146 PART B You are provided with the following; A rubber bung Vernier caliper Beam balance Proceed as follows a Using the vernier caliper, measure the length D, d and h the height of the rubber band as shown in the figure. B Measure the mass M, of the rubber bung using the beam balance.


1mk L2 50cm R2 . 1mk L3 70cm R3 . 1mk j Compute the average value of the resistance R of the bulb. 2mks www.freekcsepastpapers.comPage 117 MURANG A SOUTH MULTILATERAL EXAMS I, 2023 Kenya Certificate of Secondary Education K.C.S.E 232 1 PHYSICS PAPER 1 TIME: 2HRS INSTRUCTIONS TO CANDIDATES i Answer all questions in section A and B in the spaces below each question. Ii For numerical questions, show all your working iii Maths table and calculators may be used for calculation SECTION A 1. A salt solution of volume 30cm3 and density 1.1 g cm3 is mixed with 25cm3 of pure water of density 1g cm3. Determine a. Total mass of the mixture 1mk b. Density of the mixture 2 mks 2. The figure below shows a section of a Vernier callipers to measure the thickness of a wooden block. If the vernier calliper has zero error of. What is the actual reading of the vernier callipers 2mks 3. State the type of equilibrium for a rubber ball placed on a horizontal table as shown below 1mks 4. A ball is thrown vertically upwards and return to its starting point after 6 seconds. Calculate the maximum height reached g 10m s2 3 mks 5. A piece of paper is held in front of the mouth and air is blown horizontally over the paper.it is observed that the paper get lifted up. Explain this observation. 2mks 6. The figure below shows a uniform metre rule balancing when a mass of 200g is hung at one end. Determine the tension, T in the string. 3mks 7. A diver is 12m below the surface of water in a dam. If the density of the sea water is 1000kg m3. Determine the pressure due to the water on the diver. G 10N kg 2mks 8. A crystal of potassium permanganate was carefully introduced at the bottom of water column held in a gas jar. After sometime the whole volume of water was coloured.