⚡ Newton's Laws — Practice Worksheet

Q1. A body of mass 5 kg is acted upon by a net force of 20 N. Its acceleration is:

1. 2 m/s²
2. 4 m/s²
3. 10 m/s²
4. 100 m/s²

Q2. Newton's first law of motion defines:

1. Force
2. Inertia
3. Momentum
4. Energy

Q3. A 10 kg block rests on a frictionless surface. A horizontal force of 30 N is applied. The acceleration of the block is:

1. 0.3 m/s²
2. 3 m/s²
3. 30 m/s²
4. 300 m/s²

Q4. A person weighing 60 kg stands in a lift accelerating upward at 2 m/s². The apparent weight is (g = 10 m/s²):

1. 480 N
2. 600 N
3. 720 N
4. 780 N

Q5. Action and reaction forces act on:

1. The same body
2. Different bodies
3. The same body along the same line
4. Different bodies but not simultaneously

Q6. A bullet of mass 50 g is fired from a gun of mass 4 kg with a velocity of 200 m/s. The recoil velocity of the gun is:

1. 2.5 m/s
2. 5 m/s
3. 10 m/s
4. 25 m/s

Q7. A body of mass 2 kg is moving with velocity 10 m/s. A force is applied for 2 s and the velocity becomes 14 m/s. The force applied is:

1. 2 N
2. 4 N
3. 8 N
4. 28 N

Q8. Two blocks of masses 3 kg and 2 kg are connected by a string on a frictionless surface. A force of 10 N is applied on the 3 kg block. The tension in the string is:

1. 2 N
2. 4 N
3. 6 N
4. 10 N

Q9. A body of mass m is placed on a rough inclined plane of angle θ. The coefficient of static friction is μ. The body will start sliding when:

1. tan θ > μ
2. tan θ < μ
3. sin θ > μ
4. cos θ > μ

Q10. A rocket works on the principle of:

1. Newton's first law
2. Newton's second law
3. Newton's third law
4. Law of gravitation

Q11. A 5 kg block is on a surface with coefficient of kinetic friction 0.2. The force required to move it with uniform velocity is (g = 10 m/s²):

1. 5 N
2. 10 N
3. 15 N
4. 50 N

Q12. In a tug of war, the team that wins has:

1. Greater force on the rope
2. Greater friction with the ground
3. Greater mass
4. Greater muscular strength only

Q13. A force of 50 N acts on a body of mass 10 kg at rest. Find the velocity after 5 seconds and the distance covered.

Q14. Two masses 4 kg and 6 kg are connected by a light string over a frictionless pulley (Atwood machine). Find the acceleration and tension in the string (g = 10 m/s²).

Q15. A 2 kg block is placed on a 5 kg block on a frictionless floor. The coefficient of friction between the blocks is 0.4. Find the maximum force that can be applied on the lower block so that both move together (g = 10 m/s²).

Q16. A body of mass 0.5 kg travels in a straight line with velocity v = 3t² where t is in seconds. Find the force acting on the body at t = 4 s.

Q17. A 60 kg person stands on a weighing scale in a lift. What reading does the scale show when the lift (a) accelerates upward at 3 m/s², (b) moves at constant velocity, (c) decelerates at 2 m/s²? (g = 10 m/s²)

Q18. A 1000 kg car moving at 20 m/s brakes and stops in 5 s. Find the braking force. If the coefficient of friction is 0.5, verify using friction force (g = 10 m/s²).

Q19. Three blocks of masses 1 kg, 2 kg, and 3 kg are connected in series on a frictionless surface. A force of 12 N is applied on the 3 kg block. Find the tension between each pair of blocks.

Q20. A block of mass 4 kg is placed on a rough inclined plane of angle 30°. The coefficient of friction is 0.3. Determine whether the block slides and find the net force on it (g = 10 m/s²).