11. Which shows the correct relation between time of flight T and maximum height H ?
12. Taking off rocket can be explained by __________________?
A. 1st law of motion
B. 2nd law of motion
C. Law of conservation of momentum
D. law of conservation of energy
13. What is the angle of projection for which the range and maximum height become equal ?
A. tan-1 ¼
B. tan-1 4
C. tan-1 ½
D. tan-1 2
14. Distance covered by a freely falling body in 2 seconds will be__________________?
A. 4.9 m
B. 19.6 m
C. 39.2 m
D. 44.1 m
15. Flight of a rocket in the space is an example of______________________?
A. second law of motion
B. third law of motion
C. first law of motion
D. law of gravitation
16. At which angle the range of the projectile is maximum____________________?
17. Time rate of change of momentum is equal to____________________?
D. both A and C
18. Why Ballistic missile fails in some circumstances of precision ?
A. due to their shape
B. due to air resistance
C. due to angle of projection
D. all of these
19. A body is moving with uniform velocity. Its______________________?
A. speed changes
B. acceleration changes
C. direction of motion changes
D. displacement from origin changes
20. When velocity time graph is a straight line parallel to time axis then__________________?
A. acceleration is const
B. acceleration is variable
C. acceleration is zero
D. velocity is zero