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1. The law of conservation of momentum states that,

• A. p before is less than p after

• B. p before is the same as p after

• C. p before is more than p after

2. 2- A 0.250 kg cart moving at 0.400 m/s has how much momentum?

• A. 0.1 kg-m/s

• B. 1.0 kg-m/s

• C. 10 kg-m/s

• D. 100 kg-m/s

3. A freight train rolls along a track with considerable momentum. If it rolls at the same speed but has twice as much mass, its momentum is

• A. zero.

• B. twice.

• C. four times as much.

• D. Unchanged

4. An astronaut floating alone in outer space throws a baseball. If the ball moves away at 20 m/s, the astronaut will

• A. move in the opposite direction at 20 m/s.

• B. move in the opposite direction at a lower speed.

• C. move in the opposite direction at a higher speed.

• D. none of the above

5. If a force acting on a body causes no displacement, the work done is—

• A. -1

• B. 1

• C. 0

• D. Infinity

6. If the displacement is perpendicular to the force, then the work done is said to be—————.

• A. -1

• B. 1

• C. 0

• D. Infinity

7. The rate of doing work is called ——————-

• A. Force

• B. Acceleration

• C. Power

• D. Displacement

9. The energy possessed by the body by virtue of its motion is known as?

• A. Chemical energy

• B. Thermal energy

• C. Potential energy

• D. Kinetic energy

10. Find the potential energy stored in a ball of mass 5 kg placed at a height of 3 m above the ground.

• A. 121.20 J

• B. 147.15 J

• C. 227.31 J

• D. 182.21 J

11. What is the power utilised when work of 1000 J is done in 2 seconds?

• A. 100 W

• B. 200 W

• C. 20 W

• D. 500 W