Question

An object of mass 2 kg is sliding with a constant velocity of 4 m/s on a frictionless horizontal table. The force required to keep the object moving with the same velocity is
1. 8 N
2. 0 N
3. 5 N
4. 2 N

Answer 1

Correct Answer - Option 2 : 0 N

The correct answer is 0 N.

• Newton's first law of motion: A body doesn't change its states until an external force acts on it.
• The force is the product of mass and acceleration.
  • Force = Mass × Acceleration

Calculation: 

The body is moving with a constant velocity of 4 m/s, So acceleration in the body is zero.

⇒ Force = Mass × Acceleration

⇒ Force = 2 Kg × 0

⇒ Force = 0 N