Question

A gun of mass 2 kg recoils with a velocity of 0.1m/s while firing a bullet of mass m with a velocity of 100m/s. The mass of bullet is

Answer 1

Answer:-

Given:-

$m1 = 2kg$

$v1 = 0.1m/s$

$v2 = 100m/s$

Explanation:-

It's a case of recoil velocity.

From Law of conservation of momentum

$m1u1 + m2u2 = m1v1 + m1v1$

The initial momentum of the body is zero as the body is at rest.

$0 = m1v1 + m2v2$

substituting the values,

Note:-

The velocity of the gun should be taken as negative as it will move in opposite direction.

$0 = - 2 \times 0.1 + 100 \times m$

$- 100m = - 0.2$

$m = \frac{ 0.2}{100}$

$m = 0.2 \times {10}^{ - 2} \: kg$

or

$m = 2grams$

$\boxed{\boxed{m = 2grams}}$

so, the mass of bullet is 2 grams.