1. A boy jumps from a wall 3 m high. What is an estimate of the change in momentum of the boy when he lands without rebounding?

A. 5*100 kgms–1

B. 5*101 kgms–1

C. 5*102 kgms–1

D. 5*103 kgms–1

2. Light of wavelength 400 nm is incident on two slits separated by 1000 mm. The interference pattern from the slits is observed from a satellite orbiting 0.4 Mm above the Earth. The distance between interference maxima as detected at the satellite is

A. 0.16 Mm.

B. 0.16 km.

C. 0.16 m.

D. 0.16 mm.

3. A car moves north at a constant speed of 3 ms–1 for 20 s and then east at a constant speed of 4 ms–1 for 20 s. What is the average speed of the car during this motion?

A. 7.0 ms–1

B. 5.0 ms–1

C. 3.5 ms–1

D. 2.5 ms–1

4. An object of weight W is falling vertically at a constant speed in a fluid. What is the magnitude of the drag force acting on the object?

A. 0


C. W

D. 2W

5. An object, initially at rest, is accelerated by a constant force. Which graphs show the variation with time t of the kinetic energy and the variation with time t of the speed of the object?

6. Two stationary objects of mass 1 kg and 2 kg are connected by a thread and suspended from a spring.

The thread is cut. Immediately after the cut, what are the magnitudes of the accelerations of the objects in terms of the acceleration due to gravity g ?

7. A student of weight 600 N climbs a vertical ladder 6.0 m tall in a time of 8.0 s. What is the power developed by the student against gravity?

A. 22 W

B. 45 W

C. 220 W

D. 450 W

8. A ball of mass m strikes a vertical wall with a speed v at an angle of q to the wall. The ball rebounds at the same speed and angle. What is the change in the magnitude of the momentum of the ball?

A. 2 mvsinθ

B. 2 mvcosθ

C. 2 mv

D. zero

9. Two objects m1 and m2 approach each other along a straight line with speeds v1 and v2 as shown. The objects collide and stick together.

What is the total change of linear momentum of the objects as a result of the collision?

A. m1v1 + m2v2

B. m1v1 – m2v2

C. m2v2 – m1v1

D. zero

10. Energy is supplied at a constant rate to a fixed mass of a material. The material begins as a solid.The graph shows the variation of the temperature of the material with time.

The specific heat capacities of the solid, liquid and gaseous forms of the material are cscl and cg respectively. What can be deduced about the values of cscl and cg?

A. cs > cg > cl

B. cl > cs > cg

C. cl > cg > cs

D. cg > cs > cl




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