Question

A cricket ball of mass 150 g has an initial velocity
u ⃗ = (3iˆ + 4 ˆj)ms⁻¹ and a final velocity v ⃗ = -(3iˆ + 4 ˆj)ms⁻¹ ,
after being hit. The change in momentum (final momentuminitial
momentum) is (in kgms⁻¹)
(a) zero (b) -(0.45iˆ + 0.6 ˆj)
(c) -(0.9 ˆj +1.2 ˆj) (d) -5(iˆ + ˆj)iˆ

Answer 1

Given :-

Mass of the ball = 150 g = 0.15 Kg

v = -(3î + 4j) ms-¹

u = (3i + 4j) ms-¹

As we know that,

Momentum is the product of mass and velocity.

Change in Momentum means when a body is moving with certain velocity and have mass changes its Velocity then there is change in Momentum.

However, Impulse is also related to Momentum of body.

P = m∆V

P = m[v - u]

P = m[-(3i+4j) - (3i+4j)]

P = m[-6i - 8j]

P = 0.15[- 6i - 8j]

P = -[0.9î + 1.2j] Kg-ms-¹.