Question

A body of mass 'm' and velocity 'u' strikes a wall and rebounds with a velocity 'v'. The change in momentum is :

Answer 1

Given:

Body of mass m and velocity u strikes a wall and rebounds with a velocity v.

To find:

Change in Momentum of body.

Calculation:

Momentum is an index of a body's inertia of motion. Mathematically, it is calculated by the product of mass of the object and the instantaneous velocity.

Before hitting the wall , let Momentum be P1:

P1 = m × u .........(1)

After hitting the wall, let Momentum be P2:

P2 = m × (-v) .........(2)

Let change in Momentum be ∆P:

∆P = P2 - P1

=> ∆P = -mv - mu

=> ∆P = -m(u + v)

So, final answer is:

∆P = -m(u + v)