Question

.A gun of mass 30 Kg fires a bullet of mass 30 g with a muzzle velocity 300 m/s.
Find the recoil velocity of gun?

Answer 1

Given:-

Before Firing

• Mass of gun = 30kg

• Mass of Bullet = 30g → 0.03kg

• Initial Velocity of gun = 0m/s

• Initial Velocity of Bullet = 0m/s

After Firing

• Mass of gun = 30kg
• Mass of Bullet =30g = 0.03kg

• Final Velocity of bullet = 300m/s

To Find:-

• The Recoil Velocity of gun

Formulae used:-

• Conservation of Momentum

Now,

→ m¹ u¹ + m² u² = m¹v¹ + m²v²

• Initially the gun was at rest

→ (30) (0) + (0.03) (0) = (30) ( v¹) + (0.03)(300)

→ 0 = 30v¹ + 9

→ -9 = 30v¹

→ v¹ = -9/30

→ v = -0.3m/s

Hence, The Recoil velocity of gun is -0.3m/s