Question

A bullet of mass 40g is horizantally fired with a velocity 300m/s from a pistol of mass 4kg . what is the recoil velocity of pistol

Answer 1

Answer:

v = -0.4 m/s

Explanation:

It is given that,

Mass of the bullet, m = 40 g = 0.04 kg

Speed of the bullet, v = 20 m/s

Mass of the pistol, m' = 2 kg

Let p is the initial momentum of the system and p' is the final momentum. The initial momentum of the bullet + pistol is equal to zero because they both are at rest.

When the bullet is fired, final momentum is given by :

According to the conservation of momentum,

v = -0.4 m/s

So, the recoil velocity of the pistol is 0.4 m/s. Hence, this is the required solution.

Answer 2

Answer:

Recoil Velocity = -3m/s

Explanation:

Given:

Mass of the bullet = 40g = 0.04kg

Velocity of the bullet = 300m/s

Mass of the pistol = 4kg

Let p be the initial momentum of the system and (P) be the final momentum. The initial momentum of the bullet + pistol is equal to zero because they both are at rest.

When the bullet is fired, final momentum is given by :

P = 0.04 x 300 + 4 x v

According to the conservation of momentum,

0 = 0.04 x 300 + 4 x v

v = -3m/s

So, the recoil velocity of the pistol is -3 m/s. Hence, this is the required solution.