Question

From a rifle of mass 6kg, a bullet of mass 80g is fired with an initial velocity of

35 m/s. Calculate the initial recoil velocity of the rifle.​

Answer 1

Given:-

• Mass of Rifle , m₁ = 6kg

• Mass of bullet , m₂ = 80g = 80/1000 = 0.08Kg

• Initial velocity of bullet , u₂ = 35

• Final velocity of both bullet and Gun =0m/s

To Find:-

• Initial recoil velocity of gun ,u₁

Solution:-

By using Conservation of momentum

• m₁u₁+m₂u₂ = m₁v₁ + m₂v₂

Substitute the value we get

→ 6× u₁ + (- 0.08 × 35) = 6×0 + 0.08×0

→ 6 × u₁ -(2.8) = 0 +0

→ 6×u₁ -2.8 = 0

→ 6 × u₁ = 2.8

→ u₁ = 6/2.8

→ u₁ = 2.14m/s

∴ The initial recoil velocity of the gun is 2.14 m/s