Laws of Motion Mock Test – Class 11 Physics

1. A force pushes two blocks and on a smooth surface. If the same force is instead applied on from the opposite side, pushing toward , the contact force becomes

2. The magnitude of centripetal acceleration for speed in a circle of radius is

3. A body moving east at speeds up to east. The change in its momentum is

4. A body is constrained to move only along the -axis on a smooth horizontal track. A force component perpendicular to the track is balanced by contact forces. The useful equation for acceleration along the track is

5. A stone moving in a vertical circle is at the lowest point of its path. The required centripetal force is upward toward the centre. If the string tension is and weight is , the correct force equation at the lowest point is

6. A person stands on a scale in a lift. The scale reads . Taking , the lift is accelerating

7. In the three-block system , , on a smooth surface, a force pushes the block first. The contact force between the and blocks is

8. The table lists proposed equations for an Atwood machine with , where moves down and moves up.

The suitable row is

9. A graph description is given below.

The slope of this graph represents

10. A free-body diagram is drawn for a selected body to show

11. A block is just about to slide up a rough inclined plane because of an external force applied up the plane. The friction force acts

12. A spacecraft is far from planets and moves with constant velocity after its engines are switched off. Ignoring external forces, the motion is best explained by

13. A stationary truck has large mass but zero velocity. Its momentum is

14. Assertion: Action and reaction forces never cancel each other in the free-body diagram of one body.
Reason: Action and reaction forces act on two different bodies.

15. A pair of forces is suspected to be a Newton’s third-law pair. The strongest test is whether the forces

16. Assertion: A particle can be in equilibrium even when three forces act on it.
Reason: Equilibrium requires the vector sum of all forces to be zero, not the absence of forces.

17. A particle moving with constant velocity in a straight line under balanced forces is an example of

18. In an Atwood machine, , , and . The magnitude of acceleration is

19. A person stands on a weighing scale in a lift accelerating downward at . Taking , the scale reading is

20. A box initially moving east experiences no net force after a certain instant. Its later motion, as predicted by the inertia idea, is

21. In the early study of laws of motion, mass is introduced as a quantity connected with

22. A frame moving along a straight line has velocity for without changing speed or direction. Relative to an inertial frame, it is best described as

23. A block is pulled on a rough horizontal surface by a force making angle above the horizontal. The normal reaction is best written as

24. A object moves uniformly in a circle of radius . If its speed is , the centripetal force is

25. Newton’s second law in momentum form relates net external force to

26. In a free-body diagram of a resting book on a table, showing both “table on book” and “book on table” would be wrong because

27. A cart moving right at collides with a cart moving right at . After collision, the cart moves right at . The final velocity of the cart is

28. A block of mass on a rough inclined plane tends to slide down while connected to a light string. The tension in the string acts up the plane. At limiting equilibrium, the correct balance is

29. A force calculation uses for a body. The force in this equation must be understood as

30. A block rests on a smooth inclined plane of angle . The normal reaction is

31. In a non-uniform circular motion, the speed is decreasing while the body continues on a circular path. The tangential component of acceleration is directed

32. The table describes a two-block horizontal system on a smooth surface.

The unsuitable row is

33. For the Atwood machine with , , , and acceleration , the tension in the string is

34. A coin on a horizontal rotating disc is at radius . If the maximum static friction available is and the coin has mass , the maximum speed of the coin without slipping is

35. A data table for a body is shown.

The mass of the body is

36. A object is at rest on a rough horizontal surface. A gradually increasing horizontal force is applied. The maximum static friction is , and kinetic friction is . If the applied force is , the acceleration after motion begins is

37. A body has acceleration north. The net force on it is

38. A block on a frictionless inclined plane is analysed using axes parallel and perpendicular to the plane. The main advantage of choosing these axes is that

39. A block is on a rough incline with . It is connected to a hanging mass . Taking , , and , the minimum hanging mass needed to just pull the block up the plane is closest to

40. A student solves a lift problem and uses although the lift accelerates upward. The missing idea is that

41. A heavy trolley and a light trolley are initially at rest on a smooth horizontal floor. The same horizontal force acts on each for the same short time. The lighter trolley is expected to

42. A conical pendulum bob moves in a circle of radius with speed . If the bob has mass , the horizontal component of tension is

43. The dimension of impulse is

44. A block slides down a rough inclined plane of angle with coefficient of kinetic friction . The acceleration down the plane is

45. A block is pulled to the right on a rough horizontal floor by an applied force, but it is still at rest. The free-body diagram of the block should include

46. The normal reaction exerted by a surface on a body is always directed

47. Mass is treated as a measure of inertia because it tells how strongly a body resists

48. Assertion: A body can move with constant velocity even when the net force on it is zero.
Reason: Zero net force means zero acceleration, not necessarily zero velocity.

49. A particle in uniform circular motion has momentum of constant magnitude. Its momentum is still changing because

50. A constant horizontal force acts on a block on a rough horizontal floor. The block moves with constant velocity. The applied force must be