A man has to roll an empty drum steadily along an inclined plane from the ground to position B which is h metres above the ground as shown in the figure. In the first attempt a maximum effort F failed to roll the drum steadily to position B. What modification would you recommend so that the drum could be rolled steadily to position B with maximum effort F?

Match the functions of measuring instruments in List A with their corresponding instruments in List B by writing a letter of the correct response. List A (i) The measure of its tendency to cause a body to rotate about specific point or axis. (ii) The forces for turning a steering wheel applied by hands at opposite sides with equal forces but opposite in direction. (iii) It continues in its existing state of rest or uniform motion in a straight line, unless is changed by an external force. (iv) It is a measure of the force that can cause an object to rotate about an axis. (v) It is equal to the change of momentum of an object, when mass is constant. List B A. Couple B. Equilibrium C. Impulse D. Inertia E. Moment of a force F. Neutral equilibrium G. Stable equilibrium H. torque

1. The measure of its tendency to cause a body to rotate about specific point or axis. (1 mk)
2. The forces for turning a steering wheel applied by hands at opposite sides with equal forces but opposite in direction. (1 mk)
3. It continues in its existing state of rest or uniform motion in a straight line, unless is changed by an external force. (1 mk)
4. It is a measure of the force that can cause an object to rotate about an axis. (1 mk)
5. It is equal to the change of momentum of an object, when mass is constant. (1 mk)

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A driver uses a screw jack to support the axle of his lorry of load 5.6 kN. The screw jack has an effort arm of effective radius of 318 mm and a single-start square thread of 5 mm lead. Determine the efficiency of the jack if an effort of 70 N is required to raise the cars axle.

1. Determine the efficiency of the jack if an effort of 70 N is required to raise the cars axle. (0 mk)

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A uniform bridge 32 m long weigh 50 x 10^3 kg and a lorry weighing 15 x 10^3 kg is positioned 8 m from one end of the bridge. Considering that the weight of the bridge will act at its centre of gravity halfway along it draw the force diagram and find the force exerted on each end support of the bridge.

1. draw the force diagram and find the force exerted on each end support of the bridge. (0 mk)

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(b) By using sketches comment on the behaviour of the leaf of the electroscope when. (i) the object has negative charge. (ii) the object has positive charge.

1. the object has negative charge. (0 mk)
2. the object has positive charge. (0 mk)

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(a) Briefly describe the components of an atom. Give three elements. (i) ...................................................................................................................................................... (ii) ...................................................................................................................................................... (iii) ...................................................................................................................................................... (b) By using sketches comment on the behaviour of the leaf of the electroscope when. (i) the object has negative charge. ...................................................................................................................................................... ...................................................................................................................................................... ...................................................................................................................................................... (ii) the object has positive charge. ...................................................................................................................................................... ...................................................................................................................................................... ......................................................................................................................................................

1. Describe the components of an atom. (1 mk)
2. Briefly describe the components of an atom. Give three elements. (5 mk)
3. Give three elements. (2 mk)
4. By using sketches comment on the behaviour of the leaf of the electroscope when the object has negative charge. (2 mk)
5. By using sketches comment on the behaviour of the leaf of the electroscope when the object has positive charge. (3 mk)

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A certain mass of gas is contained in a cylinder by a piston. The temperature of the gas is 15oC pressure is 1.3 bar and its volume is 1.6 litres. The gas is allowed to expand to a volume 5.6 litres at a constant temperature and then the temperature is raised to 70oC at a constant pressure. What is the final pressure and volume of the gas.

1. What is the final pressure and volume of the gas. (0 mk)

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A force of 50 N is applied to the box containing books to make it slide over a horizontal floor. If the coefficient of friction between the box and the floor is 0.5 find the mass of the box.

1. Find the mass of the box. (5 mk)

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A man accelerated a 10 tons’ vehicle from initial velocity to a velocity of 20 m/s in 3 seconds and he found that, the kinetic energy was changed to 355 kJ. Calculate; (a) the initial velocity of the vehicle. (b) the acceleration of the vehicle.

1. the initial velocity of the vehicle. (0 mk)
2. the initial velocity of the vehicle. (5 mk)
3. the acceleration of the vehicle. (0 mk)
4. the acceleration of the vehicle. (5 mk)

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A car was driven through corrugated road at a speed of 12 m/s for 6 second and then it was accelerated for 4 seconds to a speed of 25 m/s. This speed was maintained for 4 seconds until the brake was applied for 2 seconds to stop the car. By the aid of velocity-time graph, estimate the total distance covered on this journey.

1. Estimate the total distance covered on this journey by the aid of velocity-time graph. (10 mk)

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10. (a) When a motor car tyre was tested in a garage at a temperature of 17o C was found to have a pressure of 290 ×103 Pa. assume that the volume of the air inside the tyre remains constant, what would be the value of the pressure after the tyre has been exposed in the sun so that its temperature rises to 27o C? (b) At a temperature of 27o C, a volume of air in a motorcycle tyre at a gauge pressure of 750mmHg is 3000cm3. Estimate the volume of the air inside the tyre of the motor cycle at the Standard Temperature and Pressure (S.T.P).

1. When a motor car tyre was tested in a garage at a temperature of 17o C was found to have a pressure of 290 ×103 Pa. assume that the volume of the air inside the tyre remains constant, what would be the value of the pressure after the tyre has been exposed in the sun so that its temperature rises to 27o C? (7 mk)
2. When a motor car tyre was tested in a garage at a temperature of 17o C was found to have a pressure of 290 ×103 Pa. assume that the volume of the air inside the tyre remains constant, what would be the value of the pressure after the tyre has been exposed in the sun so that its temperature rises to 27o C? (7 mk)
3. At a temperature of 27o C, a volume of air in a motorcycle tyre at a gauge pressure of 750mmHg is 3000cm3. Estimate the volume of the air inside the tyre of the motor cycle at the Standard Temperature and Pressure (S.T.P). (8 mk)
4. At a temperature of 27o C, a volume of air in a motorcycle tyre at a gauge pressure of 750mmHg is 3000cm3. Estimate the volume of the air inside the tyre of the motor cycle at the Standard Temperature and Pressure (S.T.P). (8 mk)

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