Introduction
In this post, you will learn the short questions answers of Chapter Force and Laws of Motion.


1. Which law of motion (गति का नियम) gives the measure of force?
Answer. Newton's second law of motion.

2. Name the scientists who proved for the first time that objects move with constant speed (गति) when no force acts on them.
Answer. Galileo 

3. Define 1 newton force.
Answer. 1 newton is the magnitude of force which produces an acceleration (ऐक्सेलरैशन) of 1 m/s² in a body of mass 1 kg.

4. Why do bicycles begin to slow down when we stop pedalling?
Answer. This is because of the frictional forces (घर्षण बल) acting opposite to the direction of motion.

5. Write the C.G.S unit of force.
Answer. Dyne.

6. Write the SI unit of impulse.
Answer. Ns.

7. What is the total momentum (मोमेन्टम) of a bullet and a gun before firing?
Answer. Zero.

8. Name the physical quantity that corresponds to the rate of change of (मोमेन्टम) momentum.
Answer. Force.

9. Define electrostatic force.
Answer. The force of exerted by an electrically charged body is called (विद्युत बल) electrostatic force.

10. Define force of friction.
Answer. The force acting between any two surfaces in contact and tending to oppose motion is called (घर्षण बल) force of friction.