What is momentum? Write its SI unit. Interpret force in terms of momentum. Represent the following graphically.

(a) momentum versus velocity when mass is fixed.
(b) momentum versus mass when velocity is constant

Ans. Momentum = mass � velocity
SI unit of momentum is kg ms-1
Force = Rate of change in momentum

Derive the unit of force using the second law of motion. A force of 5 N produces an acceleration of 8 ms^-2 on a mass m1 and an acceleration of 24 ms ² on a mass m2. What acceleration would the same force provide if both the masses are tied together?

F = m a = kg ms^-2 
This unit is also called newton. Its symbol is N.