Question

a) Define momentum of a body. On what factors does the momentum of a body depend? 

b) Calculate the change in momentum of a body weighing 5 kg when its velocity decreases from 20 m/s to 0.20 m/s.

Answer 1

a) Momentum is defined as the physical quantity which is the measure of the quantity of motion of a moving body. Momentum depends on the mass and velocity of the body. 

b) Mass of body = 5kg 

Velocity, v₁ = 20 m/s 

Momentum, p₁ = (20)(5) = 100 kg.m/s 

Velocity, v₂ = 0.2 m/s 

Momentum, p₂ = (5)(0.2) = 1 kg.m/s 

Change in momentum = p₂ – p₁ = 1-100 = -99 kg.m/s