September 22, 2022

Kenya Certificate of Secondary Education 2020 Physics paper 1 SECTION A 1. The diameter of a wire was measured as 2.43 mm. Name the instrument that was used to measure this diameter ( 1 mark) 2. Figure 1 shows a capillary tube dipped in mercury in a beaker. State with a reason the observation that would be made on the level of mercury in the capillary tube if the temperature of mercury is increased.(2 marks) 3. State the kinetic theory of gases.(1 mark) 4. Figure 2 shows the scale of a measuring instrument. (a) Determine the reading indicated.(1 mark) (b) State the physical quantity measured by this instrument.(1 mark) 5. Figure 3 shows a traditional stool resting on a level surface. (a) ldentify its state of equilibrium.( 1 mark) (b) State the reason for the answer in (a).( 1 mark) 6. Figure 4 shows a uniform rod AB of length 1m and weight 8N pivoted at 20 cm from one end. It is balanced by supporting it with a string attached to a fixed support. The tension in the string is 4N. Determine the position of the string from end A. (3 marks) 7. Define cohesive forces.( 1 mark) 8. Two similar containers A and B are filled with equal masses of water at the same temperature Container A is made of copper while container B is made of glass. Heat is then supplied to the containers at the same rate. State with a reason, the container in which water boils first.(2 marks) 9. Figure 5 shows a roof of a house over which wind is blowing. It was observed that, when the speed of the wind increased, the roof was blown off. Explain this observation.(2 marks) 10. Figure 6 shows the velocity-time graph of the motion of a stone thrown vertically upwards. From the graph, determine the maximum height reached by the stone.( 3 marks) 11. It is observed that when methylated spirit is poured on the palm, the palm feels colder as it dries up. Explain this observation.(2 marks) 12. Figure 7 shows a box placed on a weighing balance. The balance is placed on the floor of a lift. State what would be observed on the reading of the balance when the: (i) lift is accelerating downwards(1 mark) (ii) lift moves downwards with a uniform velocity(1 mark) (iii) lift is accelerating upwards(1 mark) 13. An object placed on the surface of water in a beaker starts to sink immediately. It is observed that it stops sinking when half of its volume is below the water surface. State the reason for this observation.(1 mark) SECTION B (55 marks) Answer all the questions in this section in the spaces provided. 14.(a) Figure 8 shows a bucket filled with water and tied to one end of a string which is used to whirl it in a vertical circular path with a uniform speed v. (i) State two forces acting on the bucket at any instant.(2 marks) (ii) Explain why the tension is lowest at point A.(2 marks) (iii) The speed of the bucket is gradually reduced. Explain what is likely to be observed when the bucket is at point A.(2 marks) (b) A stone of mass 40g is whirled at the end of a string in a horizontal circular path at (b) speed of 12ms-1. (The string and the stone are in the same horizontal plane). If the string is 1m long, determine the tension in the string.(3 marks) 15.(a) Figure 9 shows a setup used by a student to investigate how a siphon works. (a) State what would be observed when the student sucks the tube at point A and releases it. (2 marks) (b) Explain the observation in.(2 marks) (b) Figure 10 shows a test-tube inverted and floating inside a plastic bottle containing some water. The bottle is then sealed. It is observed that when the sides of the bottle are squeezed, the test-rube sinks. Explain this observation.(3 marks) (c) A metallic box weighs 188N and measures 10cm by 30 cm by 8 cm. Determine the maximum pressure it can exert when lying on one of its surfaces.(3 marks) 16.(a) Figure 11 shows a setup that can be used to verify Charles’ Law. (i) Explain how the: (I) temperature of air in the tube is measured;(2 marks) (II) volume of air in the tube is measured.(2 marks) (ii) State how the pressure is kept constant during the experiment. (iii) State how the measurements in (i) can be used to verify Charles’ law.(3 marks) (iv) State one precaution that must be taken to ensure that the temperature of air is accurately measured.(1 mark) (b) A fixed mass of gas initially at 20°C is heated at constant pressure until its volume doubles. Determine its final temperature.(4 marks) 17.(a) Figure 12 shows a simple machine. On the same figure, mark and label the following parts: (i) Effort arm(1 mark) (ii) Load arm(1 mark) (b) Figure 13 shows a pulley system used to raise a mass of 5 kg through a height of 2 m when a force of 60N is applied. (Acceleration due to gravity g is 10ms-2) Determine the: (i) distance moved by the effort;(1 mark) (ii) work done on the load;(3 marks) (iii) potential energy gained by the load (g = 10 Nkg-1).(1 mark) (c) Figure 14 shows a setup that can be used to determine the specific latent heat of vaporisation of water. A beaker containing some water was placed on a weighing balance and an immersion heater rated 500 W immersed in the water. The water was then heated until it boiled. When the water started boiling, the initial the balance was reading on noted and the stop watch started immediately. The final was then noted reading on the balance after a time t seconds. (i) State how the mass of steam can be measured using this setup.(1 mark) (ii) Write down an expression for the heat supplied by the heater.(1 mark) (iii) Determine the specific

Kenya Certificate of Secondary Education Practical 2021 Physics paper 3 Question 1 You are provided with the following: 1. A thermometer 2. A boiling tube 3. A retort stand, boss and clamp 4. A weighing balance to be shared) 5. A watch glass 6. A measuring cylinder 7. A beaker labelled X 8. A metre rule 9. An optical pin mounted on a cork 10. Water in a beaker 11. A liquid L in a beaker labelled L 12. A plane mirror 13. A stopwatch 14. Tissue paper 15. A piece of manila paper with a hole in the middle (paper cover) 16. Boiling water (to be provided) Proceed as follows: PART A a. Using the weighing balance, measure and record the mass M. of the boiling tube in grammes. b.i. Clamp the boiling tube in the retort stand. ii. Using a measuring cylinder, put 40 cm of cold water in the boiling tube and insert the thermometer in the boiling tube through the paper cover. iii. Make a hot water bath by putting approximately 500 ml of hot water into the beaker labelled X c.i. Place the boiling tube in the hot water. Using the thermometer, stir the water in the tube until the temperature rises to 48°C. (See Figure 1) (Ensure the water in the tube mixes properly to be at the same temperature) ii. With the boiling tube still clamped in the stand, remove the hot water bath. Let the water in the boiling tube cool as you stir throughout using the thermometer. iii. Immediately the temperature falls to 46°C start the stopwatch and record the time in seconds when the temperature falls to the values shown in Table 1. HINT: The time recorded is cumulative and the stopwatch should not be stopped until the time at the last temperature (40°C) is recorded. Stirring the water in the tube should also be continuous. Table 1 (Water) (3 marks)   Temperatu re (oC) 46 45 44 43 42 41 40 Time(s) d.i. Pour out the water from the boiling tube and use some tissue paper to wipe out the water in the tube. Use the measuring cylinder to put 40 cm of liquid L in the boiling tube. ii. Repeat part c(i), (ii) and (iii) using liquid L in place of water and record the results in the Table 2. Table 2 (Liquid L) (3 marks)   Temperatu re (oC) 46 45 44 43 42 41 40 Time(s) e. Use the results to determine: i. time T taken by the water to cool from 45°C to 40°C T = ……… seconds (1 mark) ii. time T, taken by liquid L to cool from 45°C to 40°C T,…………… Seconds (1 mark) iii. constant K given that K = T2/T1 (1 mark) f. Given that the densities of liquid L and water are 0.8 gcm-3 and 1.0 gcm-3 respectively determine the: i. mass ML of liquid L. (2 marks) ii. mass MW of water. (1 mark) g. Use the results to determine the constant C given that K(84Mb + 420MW ) = 84Mb + 100MLC (2 marks) PART B i. Place the watch glass on the plane mirror on the bench. ii. Clamp the optical pin horizontally in the retort stand such that its tip is vertically above the pole of the watch glass. iii. Put a little water into the watch glass. Adjust the height h of the pin above the mirror until it coincides with its inverted image tip to tip. (check for parallax to confirm). See Figure 2. iv. Measure the height h, of the pin above the mirror. h1 = ……….. cm (1 mark) v. Determine r given that r = h1/3 (1 mark) i. Pour out the water and wipe the watch glass dry. Repeat part h (iii) using liquid L instead of water i. Measure and record the height h, of the pin above the mirror. h2 = ……….. cm (1 mark) ii. Determine Z given that, Z = h2+r/h2 (2 marks) Question 2 You are provided with the following: 1. An ammeter 2. 2 cells in a cell holder 3. A coil wound on a beaker 4. A switch 5. A magnetic compass 6. A half metre rule 7. Vemier callipers (to be shared) 8. A retort stand, boss and clamp 9. A wooden block 10. Some plasticine 11. Connecting wires 12. A variable resistor labelled R Proceed as follows: a. i. Count and record the number of complete turns N of the coil on the beaker. (1 mark) ii. Use the vernier callipers to measure and record the diameter d of the beaker in metres. (1 mark) iii. Using some plasticine mount the beaker on the wooden block so that the coil is in a vertical plane. b.i. Place the compass at one end of the half-metre rule such that the E-W marks of the compass are in a direction parallel to the longest side of the half-metre rule. See Figure 3.(Use some plasticine to fix the compass so that it remains in this position throughout the experiment) ii. Clamp the other end of the rule in the stand. Adjust the height of the rule above the bench so that the height of the compass needle is approximately equal to the height of the centre of the vertical coil. iii. With the half-metre rule still clamped, rotate the stand until the north pole of the needle points at 0° of the compass (at N). (keep the stand in this position throughout the experiment) c. Move the wooden block such that the compass gets into the beaker and the centre of the coil and that of the magnetic compass needle approximately coincide (See Figure4) d. With the compass inside the beaker, now connect the coil in series with the cells, ammeter, switch and variable resistor R, as shown in Figure 5. (Ensure that the ammeter is at least 60 cm away from the compass and that there are no other magnetic materials near the compass.) e.i. Close the switch. Using the

Kenya Certificate of Secondary Education 2021 Physics paper 2 Section A (25 Marks) Answer all the questions in this section. 1. Figure 1 shows a ray of light incident on a plane mirror. Complete the diagram to show the path of the reflected ray. (1 mark) 2. Figure 2a, 2b and 2e show the process of charging an electroscope by induction It is observed that the leaf rises in (a), collapses in (b) and then rises in (c). Explain why the leaf collapses in (b). (3 marks) 3. State one use of capacitors. (1 mark) 4. Figure 3 shows a graph of magnetic strength against time for two nails P and Q when magnetised in a solenoid. P and Q are of the same size but are made of different materials. a. Identify the material that is magnetised faster. (1 mark) b. Use the domain theory to explain the answer in 4(a). (2 marks) 5. State the meaning of the term principal focus of a convex mirror (1 mark) 6. Figure 4 shows a current carrying conductor placed between the poles of two magnets. (The direction of the current is into the paper). Sketch the magnetic field produced between the conductor and the poles of the magnets. (2 marks) 7. Figure 5 shows two coherent sources of sound A and B in phase. O is a point equidistant from A and B. An observer moves from Mto N through Q. Explain what is observed at point Q. (3 marks) 8. State one factor that affects the speed of sound in water. (1 mark) 9. Figure 6 shows a ray of light incident on a prism with a critical angle of 42° Complete the diagram to show the path of the ray through the prism. (2 marks) 10. It is observed that when the heat current of the cathode ray tube is increased, the intensity of the cathode rays increase. Explain this observation. (2 marks) 11. A current of 2A flows through a bulb for 2.5 minutes. Determine the quantity of charge that flows through the bulb.(3 marks) 12. Figure 7 shows UV light passing through an aperture and incident on the cathode of a photocell. a. State what is observed on the milliammetre when the size of the aperture is increased b. State the reason for the answer in 12(a) (1 mark) 13. State the property of radio waves that makes them suitable for use in communication. (1 mark) SECTION B Answer all the questions in this section in the spaces provided. 14.a. State and explain how increase in temperature affects the conductivity of a semiconductor. (2 marks) b. Figure 8 shows a graph of potential difference (V) across a bulb against the current (I) through the bulb obtained from an experiment. Explain why parts: i. OA is straight (1 mark) ii. AB is curved. (2 marks) c. A circuit consists of 20 identical lamps connected in series to 240 V mains supply. Determine the potential difference across each of the lamps. (2 marks) d. Figure 9 shows a circuit consisting of two identical lamps and three ammeters A1, A2, and A3, connected to a cell. Given that ammeter A, reads 0.5 A: i. state the reading on Ammeter A3(1 mark) ii. explain the answer 14(d) (i). (2 marks) 15.a. State the use of the eye piece lens in a compound microscope. (1 mark) b. On the grid provided, draw a ray diagram to show how a convex lens forms a magnified real image. (3 marks) c. Figure 10 shows a defect of vision in a human eye i. State the type of defect shown. (1 mark) ii. State the type of lens that can be used to correct this defect. (1 mark) iii. On the same figure, draw rays to show how the lens in 15(c)(ii) corrects the defect. (2 marks) d. Figure 11 shows a graph of image distance (V) against the object distance (U) obtained in an experiment to determine the focal length of a concave mirror. i. Identify and mark a point X on the graph where V = U. ii. Use the point X to determine: I. the radius of curvature r. (2 marks) II. the focal length of the lens f. (1 mark) 16.a. State Faraday’s law of electromagnetic induction. (1 mark) b. Figure 12 shows a bar magnet being moved towards a solenoid. The solenoid is connected to a galvanometer. i. Indicate on the diagram the direction of the induced current in the solenoid. (1 mark) ii. Identify the pole induced at D. (1 mark) iii. Explain the answer in 16(b)(ii). (2 marks) iv. Apart from the number of tums in the solenoid, state two factors affecting the magnitude of the induced current. (2 marks) c. Explain how laminating the core of a transformer increases its efficiency. (2 marks) 17.a. Explain how a fuse protects electrical devices from damage. (2 marks) b. State and explain why the voltage in mains electricity is stepped up before long distance transmission (3 marks) c. Figure 13 shows how power can be transmitted from the generating station through transformers P, Q and R to the consumers i. Identify the type of transformer labelled P. (1 mark) ii. Explain how the number of turns in the primary and secondary coils of transformer P affects its output voltage. (3 marks) iii. State the reason why one of the wires from R to the school should be earthed. (1 mark) d. A power station generates 11 kV at a current of 1A. The voltage is stepped up to 160kV before being transmitted through electric cables. Assuming the transformer is 100% efficient, determine thie secondary current(3 marks) 18.a. Figure 14 shows a cathode ray tube. A metal plate is placed between the anode and the screen. i. State with a reason what would be observed on the screen when the cathode rays are produced (2 marks) ii. State the effect on the cathode rays produced when the anode potential is

2021 Physics paper 1 SECTION A Answer all the questions in this section in the spaces provided. 1. Figure 1 shows part of the thimble scale of a screw gauge with 50 divisions. On the diagram, draw the sleeve scale to show a reading of 3.87 mm. (1 mark) 2. Figure 2 shows a siphon used to empty a tank. In order to start the siphon, state why: a. it must be full of liquid. (1 mark) To overcome atmospheric pressure inside the siphon by expelling trapped air inside the siphon.b. end X must be below the level of the liquid in the tank. (1 mark)   To create pressure difference. 3. Figure 3(a) shows a horizontal tube containing air trapped by a mercury thread of length 5 cm. Thelength of the enclosed air column is 7.5cm. The atmospheric pressure is 76 cmHg. The tube is then turned vertically with its mouth facing down as shown in Figure 3(b). a. Determine the length 1 of the air column. (3 marks)P1V1 = P2V2 76 x 7.5 = (76 – 5)l l = 8.03cm (2 dp) b. State the reason why the mercury thread did not fall out in Figure 3(b). (1 mark) 4. In a Physics experiment, a student filled a burette with water up to a level of 15 ml. The student ran out 3 drops of water each of volume 2 cm³ from the burette into a beaker. Determine the final reading of the burette. (2 marks) Initial burette reading = 15ml Volume of water dropped out = 3 drops x 2cm³ = 6cm³ New burette reading = 15cm³ + 6cm³ = 21cm 5. State two factors that affect the angular velocity of a body moving in a circular path (marks) The instantaneous linear velocity of the moving body The radius of the circular path6. Figure 4 shows two capillary tubes X and Y of different diameters dipped in mercury. Complete the diagram to show the meniscus in Y. (1 mark) 7. In an experiment, a drop of black ink is introduced at the bottom of a container filled with water. It is observed that the water gradually turns black. State the effect on the observation when the experiment is carried out using water at a lower temperature. (1 mark)8. Figure 5 shows two identical springs arranged side by side and supporting a weight of 50 N. When the same weight is supported by one of the springs above, it produces an extension of 1 cm.Determine the effective spring constant of the arrangement in Figure 5. (3 marks) K = F/e = 50N/1cm = 50N/cm KT = 2x 50N/cm = 100N/cm or 1000N/m 9. On the axes provided, sketch a graph of density against temperature for water between 0°C and 10 °C. (1 mark) 10. State the reason why a student climbing a hill tends to bend forward. (1 mark) To shift the position of the centre of gravity to the front part to maintain equilibrium.11. Figure 6 shows a graph of temperature against time for a pure molten substance undergoing cooling. Explain what happens to the substance in region BC. (2 marks) The substance undergoes change of state from molten to solid without change in temperature.12. Figure 7 shows a uniform rod AB 2 m long and of mass 1 kg. It is pivoted 0.5 m from end A and balanced horizontally by a string attached 0.1 m from end B. Determine the tension in the string. (take g = 10 Nkg) (2 marks)Sum of clockwise moments = sum of anti-clockwise moments 10N × 0.5m = 1.4m × T T= 3.57N 13. Figure 8 shows two pieces of ice A and B trapped using a wire gauze in a large beaker containing water. Heat is supplied at the centre of the base of the beaker as shown. State the reason why B melted earlier than A (1 mark) Heated water at the bottom becomes less dense which rises to the top. Hence ice B melts earlier than A.14. Figure 9 shows a folded piece of paper. A stream of air is blown underneath the paper. Explain why the paper collapsed. (2 marks)Air blown underneath the paper reduces pressure acting on the paper. Atmospheric pressure acting from top becomes higher. Hence the paper collapses. SECTION B (55 marks) Answer all the questions in this section in the spaces provided. 15.a. Figure 10 shows a wooden block of volume 90 cm floating with 1/3 of its body submerged inwater of density 1gcm-3 (g = 10 Nkg-1) Determine:i. The weight of the block weight of block = vpg 1/3 x 90 x 1000 x 10 100000 = 0.3N Alternatively W = mg m = 1/3 x 90 x 1 = 30g W = 30 x 10 1000 = 0.3N ii. The weight of a metal block that can be placed onto the block so that its top surface is on the same level as the water surface.(3 marks) Volume of remaining part = 90 – 30 = 60cm3 U → W = vpg = 60/1000000 x 1000 x 10 = 0.6N w = mg but m = v x p 60 x 1 = 60g w = 60/1000 x 10 = 0.6N b. Figure 11 shows a solid metal suspended in oil using a thread. i. Other than upthrust, list two other forces acting on the sphere. (2 marks) Tension force Weight, mgii. The oil is carefully and gradually drawn from the beaker. State the effect on each of the two forces in 15(b)(i). (2 marks) Tension force will increase Weight, mg, will remain constant16.a. Define the term “specific latent heat of fusion” (1 mark) Quantity of heat required to change a unit mass of the material from solid state to liquid without change in temperature. b. Ice of mass 5g at a temperature of -10°C is immersed into 10.5g of hot water at 100°C in a container of negligible heat capacity. All the ice melts and the final temperature of

2.23 Physics Paper 3 (232/3) Question 1 Part A You are provided with the following: – a voltmeter – a resistance wire labelled P mounted on a metre rule. – a resistance wire labelled Q mounted on a piece of carton. – 2 dry cells and a cell holder. – 6 connecting wires, each with a crocodile clip atone end. – a switch. Proceed as follows: (a) Place the dry cells in series in the cell holder. Measure and record the total emf Eo of the cells. Eo = ————V (1 mark) (b) Connect the circuit as shown in figure 1. O is a point on P at the 50cm mark of the metre rule. A and B are points on P such thatAO = OB = X. (c) Adjust the positions of the crocodile clips A and B on P such that AO = OB = X = 25cm. Close the switch. Read and record the potential difference (V) across A0 in table 1. (d) Repeat part (c) for other values of X shown in table 1 and complete the table. (5 marks) (e) On the grid provided, plot a graph of 1 (y – axis) against l (x axis) (5 mark) (O Determine the slope S of the graph‘ (3 marks) (g) Use the slope to determine the constant h, given that h = -figii. (2 marks) Part B You are provided with the following: – a soft drawing board. – a semicircular glass block. – three drawing pins. ~ a white paper. – a liquid labelled L. – a dropper. Proceed as follows: (h) Place the white paper on the drawing board. Place the semicircular glass block on the paper and trace its outline using a pencil. (i) At the centre of the straight edge of the outline mark a point O. Also mark a point X approximately at the centre of the curved edge of the outline as shown in the figure 2. (j) Place the semicircular glass block on the outline. Push a drawing pin vertically through O into the drawing board. Ensure the pin is in contact with the glass block. Using a dropper, place two or three drops of liquid L on the pin, so that the liquid flows down the pin forming a thin film between the pin and the vertical face of the glass block. (k) View the image of the pin from point X through the glass block and move the eye round the curved surface to the right side of X until the image of the pin just disappears from view. (see figure 3) Using a second pin locate and mark a point N on the curved outline at the point where the image just disappears. (l) Repeat part (k) with the eye moving to the left side of X. Locate and mark the point M on the curved outline where the image just disappears from view. (m) Draw the lines OM and ON on the outline. (n) (i) Measure and record angle MON. (2 marks) (ii) If (The drawing bearing the candidates index number must be attached to the script). Question 2 Part A You are provided with the following: ‘ a 100ml glass beaker. – a weighing balance (to be shared). ‘ a liquid labelled L. – a measuring cylinder. ; Proceed as follows: (a) Measure and record the mass M1 of the empty beaker. M1 ……………………. ..g (1 mark) A (b) Measure and pour 2ml of liquid L into the beaker. Measure and record the mass M2 of the beaker + liquid L. M2 ………………………… ..g (1 mark) (c) Determine the density d of the liquid L. (2 marks) d = ………………………….. Part B You are provided with the following: – a retort stand, boss and clamp. – 2 boiling tubes. – a thermometer. – some distilled water in a beaker labelled W. – some liquid in a beaker labelled L. – a large beaker containing some water. – a measuring cylinder. – a stopwatch. – a tripod stand and wire gauze. – a cardboard with a hole in the middle. – a burner. Proceed as follows: (d) Clamp one boiling tube on the retort stand. Measure and pour 45ml of the distilled Water (W) into the boiling tube. Set up the apparatus as shown in figure 4. Figure 4 (e) Heat the water in the large beaker until the temperature of the distilled water reaches ‘ 85°C. Remove the boiling tube from the hot water by lifting up the retort stand and ‘ placing it a way from the burner. (f) Stir the water in the boiling tube using the thermometer. Record in the table 2 the . temperature of the distilled water at intervals of 30 seconds starting at 80°C until it drops to 60°C. (Stir the distilled water before taking any reading) (g) Using the second boiling tube, repeat the procedure in (d), (e) and (O using 45ml of liquid L instead of distilled water. Record your results in the same table. (4 marks) (h) Using the same axes on the grid provided, plot a graph of temperature (y – axis) against time for 1 (i) distilled water W. (5 marks) (ii) liquid L. (3 marks) (Lable the graphs of L and W). (i) From the graphs determine: image calculations

2.2.1 Physics Paper 2 (232/2) SECTION A (25 marks) Answer all the questions in this section in the spaces provided. 1 Figure 1, shows an object placed in front of a plane mirror. Figure A Sketch the image of the object as seen in the mirror. (1 mark) 2 Figure 2, shows two identical pithballs A and B suspended with insulated threads. They z separated by an insulator X. A is positively charged while B is negatively charged. The quantity of charge on A is three times the quantity of charge on B. Sketch on the space besides the figure, the final position of the pithballs after the insulator removed. (1 mark) 3 Figure 3, shows a voltmeter connected across two charged parallel plates. Figure 3 When a thin sheet of mica is inserted between the plates, the voltmeter reading is observed to reduce. Explain this observation. (3 marks) Figure 4, shows the cross-section of a dry cell. Use the information on the figure to answer questions 4 and 5. Figure 4 4 Name the parts labelled A and B. (2 marks) 5 State the use of the manganese (IV) oxide in the cell. (1 mark) 6 One method of producing a weak magnet is to hold a steel rod in the North South direction and then hammer it continuously for some time. Using the domain theory of magnetism explain how this method works. (2 marks) Figure 5, shows a motor connected to a magnetic switch called a relay operated by an ordinary switch S1. Use the information in the figure to answer questions 7 and 8. Figure 5 7 Explain how the relay switches on the motor when S1 is closed.(3 mark) 8 State with a reason the effect on the motor, if the iron core is replaced with a steel core and switch S, is put on and then off.(2marks) 9 Figure 6, shows standing waves on a string. It is drawn to a scale of 1:5 Figure6 (a) Indicate on the diagram the wavelength of the standing wave. (1 mark) (b) Determine the wavelength of the wave.(1 mark) 10 Figure 7 , shows two rays of light incident normally on face PQ of a glass prism, whose critical angle is 42°. Figure 7 Complete the diagram to show the paths of the two rays as they pass through the prism. (3 marks) 11 A 4Q resistor is connected in series to a battery of e.m.f 6V and negligible internal resistance. Determine the power dissipated by the resistor. (2 marks) 12 Table l shows radiations and their respective frequencies. Arrange the radiations in the order of increasing energy. (1 mark) 13 State the reason why electrical power is transmitted over long distances at very high voltages. (1 mark) 14 State the meaning of the term “threshold frequency” as used in photoelectric emission. (1 mark) SECTION B (55 marks) Answer all the questions in this section in the spaces provided. 15 (a) Figure 8, shows a graph of potential difference V (volts) against a current 1 (amperes) for a certain device. From the graph: (i) state with a reason whether or not the device obeys ohms law. (2 marks) (ii) determine the resisttmce of the device at; (ii) I = 1.5A (2 marks) (iii) l = 3.5A (2 marks) (iv) From the results obtained in -(ii) state how the resistance of the device varies as the current increases. (1 mark) (iv) State the cause of this variation in resistance. (1 mark) (b) Three identical dry cells each of e.m.f. 1 .6V are connected in series to a resistor of 11.49. A current of 0.32A flows in the circuit. Determine: (i) the total e.m.f. of the cells; (1 mark) (ii) the internal resistance of each cell: (3 mark) 16 (a) State the meaning of the term “principal focus” as applied in lenses. (1 mark) (b) You are provided with the following apparatus to determine the focal length of a lens: – a biconvex lens and lens holder. – a lit candle. – a white screen. – a metre rule (i) Draw a diagram to show how you would arrange the above apparatus to determine the focal length of the lens (1 mark) (ii) Describe the procedure you would follow. (1 mark) (iii) State two measurements that you would take. (2 marks) (iv) Explain how the measurements in (m) would be used to determine the focal length. (2 marks) (c) An object is placed 30cm in front of a concave lens of focal length 20cm. Determine the magnification of the image produced. (4 marks) 17 (a) State what is meant by the term “electromagnetic induction”. (1 mark) (b) Figure 9, shows a simple electric generator Figure 9 (i) Name the parts labelled P and Q. (2 marks) P ……………. Q ……………. (ii) Sketch on the axes provided, a graph to show how the magnitude of the potential difference across R, changes with the time t. (1 mark) (iii) State two ways in which the potential difference produced by such a generator can be increased. (2 marks) (c) In a transformer, the ratio of primary turns to the secondary turns is 1:10. A current of 500mA flows through a 20052 resistor in the secondary circuit. Assuming that the transformer is 100% efficient, determine: (i) the secondary voltage; (1 mark) (ii) the primary voltage; (2 marks) (iii) the primary current. (2 marks) 18 (a) State two differences between cathode (b) Figure 10, shows the main features of a cathode ray oscilloscope (CRO). Figure 10 (i) Name the pans labelled M and N.(2 marks) N ……………. M……………… rays and electromagnetic radiations. (ii) Explain how electrons are produced in the tube. (2 marks) (iii) When using the CRO to display wave forms of voltages, state where the following should be connected: (i) the voltage to be displayed on the screen; (1 mark) (ii) the time base voltage. (1 mark) (iii) state why the tube is highly evacuated. (1 mark) (c) Figure 11, shows the waveform of a voltage

KCSE Past Papers Physics 2011 2.2.2 Physics Paper 1 (232/1) SECTION A (25 marks) Answer all the questions in this section in the spaces provided. 1 Figure 1 shows a lorry moving on an inclined section of a straight road. At the back is a chain hanging from a point on a horizontal axis through the cenne of gravity of the lorry. Figure 1 State with a reason whether the lorry is stable or not stable. (1 mark) 2 State the constant force that opposes the motion of a stone initially at rest, as it falls through air from a tall building. (1 mark) 3 Figure 2 shows a spring balance. It’s spring constant is l25Nm”. The scale spreads over Determine the maximum weight that can be measured using this spring. (3 marks) 4 Figure 3 shows an aluminium tube tightly stuck in a steel tube. Figure 3 Explain how the two tubes can be separated by applying a temperature change at the junction given that aluminium expands more than steel for the same temperature rise. (2 marks) 5 Figure 4 shows two identical beakers P and Q full of water at 90°C. Two similar cold wet clothes are wrapped, one around the top of P and the other around the bottom of Q. Figure 4 State with a reason, the beaker in which the water cools faster. (2 marks) 6 Figure 5 is a graph of net force on a body against it’s velocity as it falls through a liquid. Determine the terminal velocity of the body. (1 mark) 7 Figure 6 shows a small toy boat floating on water in a basin. X and Y are two points near the toy. Figure 6 When a hot metal rod is dipped into the water at point X, the toy is observed to move towards Y. Explain this observation. (2 marks) 8 When the temperature of a gas in a closed container is raised, the pressure of the gas increases. Explain how the molecules of the gas cause the increase in pressure. (2 marks) 9 Figure 7 shows part of a petrol engine, in which air flowing under atmospheric pressure passes into a constriction, where it mixes with petrol. The mixture then flows into a combustion cylinder. Figure 7 Explain what causes the petrol to move from the petrol chamber to the air stream in the constriction when the piston is moved downwards. (2 marks) 10 State the reason why it is easier to separate water into drops than to separate a solid into smaller pieces. (1 mark) Figure 8 shows a uniform wooden block of mass 2kg and length 25cm lying on a bench. It hangs over the edge of the bench by 10cm. Use the figure to answer questions 11 and 12. Figure 6 11 Indicate on the figure two forces acting on the wooden block. (1 mark) 12 Determine the minimum force that can be applied on the wooden block to make it turn about the edge of the bench. (2 marks) 13 A particle starts from rest and accelerates uniformly in a straight line After 3 second it is 9m from the starting point. Determine the acceleration of the particle. (3 marks) 14 Figure 9 shows a syringe full of water. It has two identical holes A and B drilled along it s cylinder. The cylinder nozzle is closed. Figure 9 State with a reason how the speeds of the jets of water from A and B compare when the piston is pushed into the cylinder. (2 marks) SECTION B: (55 marks) Answer all the questions in this section 15 Figure 10 shows a simple pendulum of length 80cm. The pendulum bob whose mass is 50g oscillates between points A and B, through its rest position C. A and B are both 10cm higher than C. Figure 10 (a) (i) Indicate with an arrow, on the path ACB, the direction of the greatest velocity of the bob as it moves from A to BA (1 mark) (ii) State the form of energy possessed by the pendulum bob at point A. (1 mark) (b) Determine: (i) the velocity of the bob at point C, (3 marks) (ii) the tension in the string as the bob passes point C. (3 marks) (take acceleration due to gravity g = 10 III/S2) (c) After some time, the pendulum comes to rest at point C. State what happens to the energy it initially possessed. 16 Figure 11 shows a stone attached to the end of a string with a uniform speed of 2m/s When the stone reaches point X on the circle, the string breaks. Figure 11 (i) indicate on the diagram with an arrow, the direction of the motion of the stone when the string breaks. (1 mark) (ii) State the magnitude of the velocity after the string breaks. (1 mark) (iii) Give a reason for your answers in (i) and (ii). ” (1 mark) (b) Figure 12 shows a lorry towing a trailer using a rope. Figure 12 The lorry exerts a force N on the trailer and the trailer exerts an equal but opposite force M on the lorry. The frictional force between the trailer and the road is F. Explain how the forces N, M and F enable the trailer to move. (2 marks) (c) Figure 13 shows a friction less trolley of mass 2kg moving With uniform velocity towards a wall. At the front of the trolley is a spring whose spring constant is 25N/m . The trolley comes to rest momentarily after compressing the spring by 3cm and then rebounds from the wall. Figure 13 (i) Determine (ii) the force exerted on the Wall by the spring. (3 marks) (iii) the maximum acceleration of the trolley as it rebounds from the wall. (3 marks) (ii) State the reason why the trolley acquires a constant velocity alter it rebounds (2 marks) 17 (a) When the temperature of water reaches the boiling point, bubbles rise to the surface. (i) State

Physics Paper 3 (232/3) Question 1 . This question consists of two parts A and B; attempt both parts. PART A You are provided with the following: – a pendulum bob – a stop-watch – two metre rules – two retort stands, two bosses and two clamps. – some thread. Proceed as follows: (a) Clamp one metre rule horizontally on the two stands so that the graduations are in a vertical plane. Suspend the pendulum bob from the metre rule with two pieces of thread so that the length of each thread from the point of support on the metre rule to the pendulum bob is 50 cm. See figure 1. The length of each thread will remain 50 cm throughout the experiment. The height of the metre rule above the bench should be at least 65 cm. (4 marks) (d) (i) Plot a graph of T4 (y – axis) against d2. (4 marks) in a plane perpendicular to the length of the metre rule and release it so that it oscillates (c) Repeat the procedure in (b) for other values of d shown in table 1. Complete the table. Table 1 (ii) Determine the slopes S of the graph. (2 marks) , determine the value of K. (2 marks) PART B You are provided with the following: – one meter rule – a piece of thread – stop watch Proceed as follows. (e) Using the meter rule measure the length L and breadth b for the magnet. L = ……………………………… b = ……………………………… (1 mark) (f) Use the balance to measure the mass M of the magnet. M = ……………………………. kg. (1 mark) (h) Clamp the meter rule between the two resort stands. Using a piece of thread suspend in a horizontal plane as shown in figure 2. Keep away all unnecessary magnetic materials including voltmeter form this a vertical axis through its centre as shown by the arrows. Measure the time t for (a) t = ………………………….. (II) Determine the period T of the oscillations. (1 mark) G Question 2 This question consists of two parts A and B, attempt both parts. PART A You are provided with the following – a voltmeter – a capacitor – a switch – a stop watch – five connecting wires – two cells and a cell holder Proceed as follows: (a) Connect the circuit as shown in figure 3. Make sure that the terminals of the capacitor and those of the battery are correctly connected, capacitor. the stop watch simultaneously. Stop the stopwatch when the voltage has (d) Reset the stopwatch and close the switch. Repeat the procedure in (c) to of the other values shown in table 2. Table 2 (e) (i) On the grid provided, plot a graph of Voltage V (y-axis) against time t, (4 marks) t =…………………. seconds (1 mark) (1 mark) 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,p> – one stand, one boss and one clamp – a beaker Proceed as follows: (g) 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). (h) Using another piece of thread suspend the glass prism from the meter rule at a point 35 cm from O. Suspend the 50 g mass on the opposite side of O using another piece of thread. Adjust the position of the thread attached to the 50 g mass until the metre rule balances once more. See figure 4. mass. l1 = …………………… cm (1 mark) (Take g = 10 N kg-1) (1 mark) (i) Put cold water into the beaker (approximately three quarter ( 3 4 full). With the glass balances when the prism is fully submerged in the cold water. See figure 5. (I) l2 = …………………….. cm (1 mark) (II) Determine the weight W2 of the prism in the cold water. (1 mark) (j) Measure and record the temperature T1 of the cold water when the system is balanced. T1 = …………………….. oC (1 mark) (k) Now pour out the cold water and replace it with hot water. Balance the metre rule at 35 cm from 0. is submerged in hot water. l3 = …………………. cm. (1 mark) (ii) Measure and record the temperature T2 of the hot water. T2 =……………………. oC (1 mark) (iii) Determine the weight W3 of the prism in hot water. (1 mark) (l) Determine the constant k for the water given that: k = (w1 – w2) – (w1 – w3) (w1 – w3) ( T2 – T1) (2 marks)    

 Physics Paper 2 (232/2) SECTION A (25 marks) Answer all the questions in this section. 1 State the reason why when a ray of light strikes a mirror at 900, the reflected ray travels along the same path as the incident ray. (1 mark) 2 Explain why the image formed in a pin hole camera gets blurred when the hole is enlarged. (2 marks) 3 State the reason why the magnetic field strength of a magnet is greatest at the poles. (1 mark) 4 Figure 1 shows a cell of e.m.f. 2 V connected in series with a resistor R and a switch S. (a) State the reading of V1 with S open. (1 mark) (b) With S closed, V1 reads 1.6 V. State the reading of V2. (1 mark) 5 centre of curvature of the mirror. Complete the diagram to show: (a) how incident rays are reflected to form the image; (2 marks) (b) the object position. (1 mark) 6 Figure 3 shows a ray of light passing into a glass prism ABC. (a) Determine the values of a and b. (1 mark) (b) Identify X. (1 mark) 8 Figure 4 shows a simple transformer connected to a 12 V a.c. source and an a.c. voltmeter. By counting the number of turns in each coil, determine the reading on the voltmeter. 9 In domestic wiring systems lamps in the lighting circuit are required to be in parallel and not in are connected in series with a switch, a cell and a milliameter. observation. (2 marks) burning wood is cut off by the glass sheet. (2 marks) 12 A photon of ultraviolet light having energy E falls on a photoemissive surface whose work function is T. Write an expression for the maximum kinetic energy of the resulting photoelectron in terms of E and T. (1 mark). 13 When a germanium crystal is doped with arsenic, it becomes an N-type semiconductor. Explain how this change occurs. (2 marks) (Number of electrons in the outermost shell for germanium = 4, Arsenic = 5) SECTION B (55 marks) Answer all the questions in this section. 14 Figure 6 shows two convex lenses A and B used to produce a magnified virtual image of an object. (a) Determine the focal length of lens A. (Take 1unit to represent 10cm). (b) State the function of: (i) lens A (1 mark) (ii) lens B (1 mark) (c) State how the functions in (b) are achieved by: (i) lens A (1 mark) (ii) lens B (1 mark) (d) Determine the magnification produced by: (i) lens A; (2 marks) (ii) the whole system. (2 marks) 15 (a) Explain how a positively charged electroscope gets discharged when the cap is touched with a finger. (2 marks) (b) Figure 7 shows capacitors A and B connected in series with a battery of e.m.f 4 V. Determine: (i) the effective capacitance of the circuit. (3 marks) (ii) the quantity of charge in capacitor A. (3 marks) (iii) the quantity of charge in capacitor B. (1 mark) (c) Figure 8 shows an isolated negative point charge Q. On the figure, sketch the electric field pattern around the charge. (2 marks) 16 (a) Two points A and B have a potential difference of V volts. Q coulombs of charge flow (i) the electrical energy transformed between the two points in terms of Q. (1 mark) (ii) the power transformed in terms of Q and t. (1 mark) (iii) show that the power transformed is given by P = IV. (2 marks) (b) The lighting circuit in a house has 20 lamps each rated 60 W, 240 V. Determine whether a fuse rated 4 A can be used in the circuit when all the lamps are put on. (4 marks) 17 (a) Figure 9 shows a cathode ray tube in which a beam of electrons is cast on the screen. Figure 9 (i) state how the electrons are produced in the tube. (1 mark) (ii) state how the electron beam is detected. (1 mark) (iii) State the reason for having a variable potential difference (p.d.) at the: (I) grid; (1 mark) (II) anodes. (1 mark) (b) Figure 10 shows the waveform of a signal applied at the y-plates of an oscilloscope whose time-base is switched to the scale of 2 milliseconds per centimeter. Determine: (i) the period of the signal; (2 marks) (ii) the frequency of the signal. (3 marks) 18 (a) Figure 11 shows plane light waves in air incident on a convex lens whose principal focus is F, the waves move past point G. Complete the diagram to show the pattern of the emergent waves between the lens and point G. (2 marks) (b) Figure 12 shows crests of circular water waves spreading from two points A and B Figure 12 Given that the amplitude of each wave is 5 cm, state with a reason the amplitudes of the (i) C; (2 marks) (ii) D. (2 marks) (c) Figure 13 shows a standing wave formed when a string of length 1.5 m stretched between two supports is plucked in the middle. Figure 13 (i) Explain how the standing wave is formed. (3 marks) (ii) Determine the wavelength of the standing wave. (1 mark) coils in series. 19 On the figure, indicate (i) the north and south poles of the resulting magnet (1 mark) (ii) the complete magnetic field pattern between the poles. (1 mark) (b) Figure 15 shows the permanent magnet made in part (a) above. A coil wound loosely on the middle limb is connected in series with a low voltage a.c. and a switch. State and explain the observation made on the coil when the switch is closed. (2 marks) positively charged. (i) Name the electrolyte in the cell. (1 mark) (ii) Explain how: (I) Zinc gets negatively charged. (1 mark) (II) Copper gets positively charged (1 mark) (iii) State what constitutes the current when a wire is used to connect the zinc plate and the copper plate externally.

.1 Physics Paper 1 (232/1) SECTION A (25 marks) Answer all the questions in this section in the spaces provided. 1 Figure 1 shows part of the main scale and vernier scale of a vernier callipers. Figure 1 Record the reading indicated. (1 mark) 2 State one factor that affects the turning effect of a force on a body. (1 mark) 3 Figure 2 shows some air trapped by mercury in a glass tube. The tube is inverted in a dish containing mercury. Figure 2 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. (3 marks) 4 An object of weight 20 N attached at the end of a spring causes an extension of 0.5 cm on the spring. (a) Determine the spring constant of the spring. (2 marks) (b) Determine the weight of an object that would cause an extension of 0.86 cm when attached at the end of the same spring. (1 mark) 5 State two measurements you would take in an experiment to determine the upthrust of an object which is immersed in a fluid. (2 marks) 6 State how the measurements in question (5) are used to determine the upthrust of the object. (1 mark) 7 Figure 3 shows a piece of wood fitted into a copper pipe and a piece of paper wrapped tightly around the junction. Figure 3 It is observed that when a flame is applied around the paper at the junction, the side of the paper around the wood burns first. Explain this observation. (2 marks) 8 Figure 4 shows a uniform metre rule of weight I N with two weights of 0.18 N and 0.12 N suspended from its ends. Figure 4 Determine how far from the 0.18 N weight a pivot should be placed in order to balance the meter rule. (3 marks) 9 Explain why brakes fail in a hydraulic braking system when air gets into the system. 10 Figure 5 shows a Bunsen burner. Figure 5 Explain how air is drawn into the burner when the gas tap is open. (3 marks) 11 Figure 6 (a) and 6(b) show capillary tubes inserted in water and mercury respectively. It is observed that in water the meniscus in the capillary tube is higher than the meniscus in the beaker, while in mercury the meniscus in the capillary tube is lower than the meniscus in the beaker. Explain these observations. (2 marks) 12 State why it is necessary to leave an air space in a closed glass bottle of water when it is to be kept in a refrigerator. (1 mark) 13 A drop of blue ink is introduced at the bottom of a beaker containing water. It is observed that after some time, all the water in the beaker turns blue. Name the process that takes place. (1 mark) SECTION B (55 marks) Answer all the questions in this section in the spaces provided. 14 (a) State two ways in which the centripetal force on a body of mass m can be increased (2 marks) (b) Figure 7 shows an object at the end of a light spring balance connected to a peg using a string. The object is moving in a circular path on a smooth horizontal table with a constant speed. Figure 7 (i) State what provides the centripetal force. (1 mark) (ii) Indicate with an arrow on the figure the direction of the centripetal force. (1 mark) (iii) State a reason why the object is accelerating while its speed remains constant. (1 mark) (iv) Given that the mass of the object is 0.5 kg and it is moving at a speed of 8 ms-1 at a radius of 2 m, determine the reading on the spring balance. (3 marks) (c) A stone thrown vertically upwards reaches a height of 100 m. Determine the: (i) initial velocity of the stone. (2 marks) (Neglect air resistance and take g = 10 ms-2) (ii) total time the stone is in air. (2 marks) 15 (a) State the meaning of the term “specific latent heat of fusion”. (1 mark) (b) Figure 8 shows a set up of apparatus used in an experiment to determine the specific latent heat of fusion of ice. Figure 8 The following readings were noted after the heater was switched on for 5 minutes: – mass of beaker = 130 g – mass of beaker + melted ice = 190 g (i) Determine the: (I) energy supplied by the 60 W heater in the 5 minutes. (3 marks) (II) specific latent heat of fusion of ice. (4 marks) (ii) It was observed that some of the crushed ice melted even before the heater was switched on. State a reason for this observation. (1 mark) 16 (a) A horizontal force of 12 N is applied on a wooden block of mass 2 kg placed on a horizontal surface. It causes the block to accelerate at 5 ms-2. Determine the frictional force between the block and the surface. (3 marks) (b) Figure 9 shows a graph of velocity against time for a ball bearing released at the surface of viscous liquid. Figure 9 Explain the motion of the ball bearing for parts (i) OA (2 marks) (ii) AB (2 marks) (c) Figure 10 shows a pulley system used to raise a load by applying an effort of 500 N. Figure 10 State the: (i) velocity ratio of the system. (1 mark) (ii) purpose of pulley 2. (1 mark) (iii) Given that the machine has an efficiency of 80%, determine the maximum load that can be raised. (3 marks) 17 Figure 11 shows an insulated cylinder fitted with a pressure gauge, a heating coil and a frictionless piston of cross-sectional area 100 cm2. Figure 11 (a) While the piston is at position O, the pressure of the enclosed gas is 10 Ncm-2 at a temperature of

3.5.3 Physics Paper 3 (232/3) Question 1 PART A You are provided with the following: a metre rule 3 optical pins 2 small wooden blocks a stop watch a stand, a boss and clamp a piece of sellotape Proceed as follows: a) Using the two wooden blocks, clamp two optical pins about 4 cm apart in the stand so that they project out of the blocks in a horizontal plane. (b) Using a piece of sellotape, attach the third optical pin across the metre rule at a distance x = 1O cm from the 50 cm mark. Now suspend the metre rule on the two clamped pins so that it can swing freely in a vertical plan with the third pin as the axis. (See figure 1) (c) Displace the lower end of the metre rule slightly and let it oscillate as shown in the figure 1. Measure and record in table l the time t(s) for 20 oscillations. (Correct to one decimal place). (d) (i) Repeat the procedure in (b) and (c) for the values of X shown in table 1. (ii) For each value of x shown in the table, determine the period T(s), correct to two decimal places, and complete the table. (The period T is the time for one complete oscillation). (e) On the grid provided, plot a graph of T2X(y-axis) against X2 (origin not required). (5 marks) (f) From the graph, determine: (i) the slope S of the graph. (3 marks) (ii) the value of constant r given that: rS = 39.5 (2 marks) PART B You are provided with the following: – a converging mirror – a rectangular piece of manilla paper – a half meter rule – a stand, boss and clamp – a dropper – liquid Q Proceed as follows: (g) (i) Using the wooden blocks clamp the manilla paper in the stand so that it projects out of the blocks in a horizontal plane, about 30 cm above the bench. (ii) Place the mirror on the bench so that its centre is vertically below the free end of the manilla paper. (h) With your eye vertically above the free end of the manilla, observe its inverted diminished image appearing as in figure 2. (i) Now adjust the height of the manilla vertically above the centre of the mirror until its width and that of the inverted image are equal as in figure 3. Measure and record the distance L1 between the manilla paper and the bench. L1 = …………………….. ..cm (1 mark) (j) Using the dropper provided put some liquid Q on the mirror so that its surface is about 3 cm in diameter. Repeat part (i). Measure and record the distance L2 between the manilla paper and the bench. L2 : ……..cm (1 mark) (k) Determine constant k given that: L1 = kL2 (2 marks) Question 2 You are provided with the following: four 10 Q resistors a resistance wire labelled S mounted on a half metre rule a resistance wire AB mounted on a metre rule two dry cells and a cell holder a centre zero galvanometer G 8 connecting wires each with a crocodile clip at one end a jockey a micrometer screw gauge a switch (a) Set up the circuit as in figure 4 in which R is nearA and S is near B. (R is a 10 Q resistor or an appropriate combination of 10-ohm resistors). (b) Starting with a single 10 Q resistor as R, close the switch. Using the jockey tap wire AB briefly near end A and observe the deflection on the galvanometer. Now tap the wire near end B and again observe the deflection of the galvanometer. (The two deflections should be in opposite directions) (c) Still with the 10 Q resistor as R, tap at various points along wire AB to obtain a point P at which the galvanometer shows zero deflection. Measure and record in table 2 the length L (m) between A and P. (Record L correct to 3 decimal places) (d) Repeat part (c) to obtain L for other values of R shown in table 2. (6 marks) Determine: (i) 1/L for all the values of L correct to 2 decimal places. (1 mark) (ii) 1/R for all values of R correct to 3 decimal places. (1 mark) On the grid provided, plot a graph of 1/L (y-axis) against 1/R (origin not required). (5 marks) (i) Determine the slope n of the graph. (3 marks) (ii) State the unit of n. (1 mark) Using the micrometer screw gauge, measure and record the diameter D of wire S in metres. D : …………………………. .. m. (1 mark) Determine the value of constant k given that 4k=rnD2n(3 marks)