Name. School Index No.. Candidate s sign. Date. 232/1 PHYSICS Paper 1 July/August 2010 2 Hours MANGA DISTRICT JOINT EVALUATION TEST 2010 Kenya Certificate of Secondary Education (K.C.S.E) 232/1 PHYSICS Paper 1 July/August 2010 2 Hours Instructions to candidates. 1. Write your name and index number in the spaces provided above 2. Sign and write the date of examination in the spaces provided above 3. This paper consists of two sections: A and B 4. Answer all the questions in section A and B in the spaces provided 5. All working must be clearly shown 3. Mathematical tables and silent electronic calculators may be used. Take acceleration due to gravity g = 10ms -1 FOR EXAMINER S USE ONLY. SECTION MAXIMUM SCORE CANDIDATES SCORE A 1 12 25 13 09 14 10 B 15 12 16 15 17 09 TOTAL SCORE 80 1
This paper consists of 12 printed pages. Candidates should check the question paper to Ensure that all the pages are printed as indicated and no questions are missing. SECTION A (25 MARKS) Answer ALL the questions in this section in the spaces provided 1. The vernier calipers shown in figure 1 has a zero error of +0.05cm What reading is indicated by the instrument 2. State two factors on which the extension of a wire depends on assuming it obeys Hooke s Law 3. Figure 2 show a solid cone which has a uniform density in equilibrium Determine the weight of the cone (3mks) 2
4. A hot air balloon is tethered to the ground on a windless day as shown in figure 3 The envelope of the balloon contains 1200m 3 of hot air of density 0.8kg/m 3. Mass of the empty balloon is 400kg. Density of the surrounding air is 1.3kg/m 3. Calculate the tension in the rope holding the balloon on the ground (3mks) 5. A wooden bench and a metal bench are both left in the sun for a long time. Explain why the metal bench feels hotter to touch 6. Figure 4 shows a manometer attached to a gas supply. If the atmospheric pressure is 1.0336 x 10 5 Pa. Calculate the pressure of the gas supply. (Density of mercury = 13600kg/m 3 ) 3
7. A student states that when two bodies at different temperatures are brought into contact the resulting rise of temperature in one will be equal to the fall in temperature in the other. Give two reasons why this statement is wrong 8. A thin layer of water underneath a beaker containing ether freezes when air is blown through ether. Explain why the water freezes. (1mk) 9. A boy of mass 58kg jumps with a horizontal velocity of 3ms -1 onto a skateboard of mass 2kg (See figure 5) 4
What is his velocity as he moves off on the skateboard. 10. Water flows along a horizontal pipe of cross sectional area 30cm 2 at a speed of 40ms -1. It reaches a section where the speed is 7.5ms -1. Find the area of this section of the pipe 11. An object dropped from a height h, attains a velocity of 6ms -1 just before hitting the ground. Calculate the value of h. 12. Below is a velocity time graph describing the motion of a particle 5
Determine the total displacement of the particle in the first 20 seconds SECTION B (55 MARKS) Answer all the questions in this section in the spaces provided 13. A block and tackle is made up of three pulley wheels on top and two pulley wheels at the bottom in figure 6 6
(a) Complete the diagram by drawing the chain which passes over the wheels and indicate where the effort is applied (b) What is the velocity ratio (V.R) of the machine (1mk) (c) A load of 1120N is lifted by an effort of 250N Determine (i) The mechanical advantage (M.A) of the system (1mk). (ii) The efficiency, E, of the system (d) How much percentage energy is wasted in the above system (1mk) 7
(e) Using the axes given below, sketch a graph of efficiency, E, against load 14. (a) Define specific latent heat of fusion of a substance (1mk). (b) Water of mass 200g at a temperature of 60 o C is put in a well lagged copper calorimeter of mass 80g. A piece of ice at 0 o C and mass 20g is placed in the calorimeter and the mixture stirred gently until all the ice melts. The final temperature of the mixture is then measured (Latent heat of fusion of ice = 33400Jkg -1, specific heat capacity of water = 4200Jkg -1 K -1 ) Determine: (i) The heat absorbed by the melting ice at 0 o C (ii) The heat absorbed by the melted ice (water ) to rise to temperature T (iii) The heat lost by the warm water and the calorimeter (Specific heat capacity of the calorimeter = 900Jkg -1 K -1 ) 8
(iv) The final temperature T of the mixture (3mks). 15. (a) A motor car tyre is inflated so that the pressure is2 x 10 5 Nm -2 at a temperature of 17 o C. During a journey the tyre heats up to 47 o C, what will be the new pressure? (Assume that the tyre does not expand) (3mks). (b) Table 1 shows the results from Boyles Law experiment Pressure (atmosphere) Length of air column, L (mm) 1 / L x 10-2 (mm -1 ) 1 1.3 1.5 1.8 2.3 2.6 3.2 3.7 41 30 27.5 22 18 16 12.5 11.0 (i) Complete the table by filling in the values of the last two rows (ii) Plot a graph of pressure against 1 / L on the grid provided (5mks) 9
(iii) Estimate the pressure of the air column when the length of the air is zero. 16. Figure 7 shows a graph of velocity against time for a moving body (a) (i) Describe the motion between O and B (ii) Determine the acceleration between B and C (b) A body moving initially at 50ms -1 decelerates uniformly at 2ms -2 until it comes to rest. What distance does it cover from the time it started to decelerate (3mks) (c) A car of mass1200kg is moving with a velocity of 25ms -1 round a flat bend of radius 150m. Determine: 10
(i) The minimum frictional force between the tyres and the road that will prevent the car from sliding off. (ii) Coefficient of limiting static friction between the tyres and the surface. (d) The initial velocity of a body of mass 50kg is 10ms -1. A constant resultant force of 15N is then applied. How long will it take before the kinetic energy doubles (4mks) 17. An object of mass 0.5kg is attached to one end of a light inextensible string and whirled in a vertical circle of radius 1.0m and centre O as in figure 8 11
If the tension on the string when the object is at the lowest position, A is 13.0N Calculate; (a) The velocity V of the object (4mks) (b) The tension on the string when the object is at the highest point C of the circle (3mks) (c) Explain why a pail of water can be swung in a vertical circle without the water pouring out 12 END