1. When a bus suddenly takes a turn, the passengers are thrown outwards because of ?
2. A person sitting in an open car moving at constant velocity throws a ball vertically up into air. The ball fall ?
3. A train is moving with velocity 20 m/sec. on this, dust is falling at the rate of 50 kg/min. The extra force required to move this train with constant velocity will be ?
4. Two forces are such that the sum of their magnitudes is 18 N and their resultant is perpendicular to the smaller force and magnitude of resultant is 12. Then the magnitudes of the forces are ?
5. The resultant of two forces, one double the other in magnitude, is perpendicular to the smaller of the two forces. The angle between the two forces is ?
6. A weightless ladder, 20 ft long rests against a frictionless wall at an angle of 60o with the horizontal. A 150 pound man is 4 ft from the top of the ladder. A horizontal force is needed to prevent it from slipping. Choose the correct magnitude from the following ?
7. A cricket ball of mass 150 gm is moving with a velocity of 12 m/s and is hit by a bat so that the ball is turned back with a velocity of 20 m/s. The force of blow acts for 0.01s on the ball. The average force exerted by the bat on the ball is ?
8. You are on a frictionless horizontal plane. How can you get off if no horizontal force is exerted by pushing against the surface ?
9. A ball of mass 150g moving with an acceleration 2 20m / s is hit by a force, which acts on it for 0.1 sec. The impulsive force is ?
10. A force of 50 dynes is acted on a body of mass 5 g which is at rest for an interval of 3 seconds, then impulse is ?