Question

A bullet of mass 100 g is fired with velocity of 700 metres per second usin a gun of mass 5 kg.Calculate the recoil velocity of the gun

Answer 1

Given :

• Mass of bullet = 100 g

• Velocity of bullet = 700 m/s

• Mass of gun = 5 kg

To find :

• Recoil velocity of gun

Solution :

Here, firstly we shall convert the mass of the bullet from grams into kilograms.

As we know,

• 1 kg = 1000 g

Divide the value by 1000 to convert it from kg into g.

→ Mass = 100 ÷ 1000

→ Mass = 1 ÷ 10

→ Mass = 0.1

Therefore, mass of the bullet = 0.1 kg

Now, calculating the recoil velocity of the gun :-

→ Mass of bullet × Velocity of bullet = Mass of gun × Recoil velocity of gun

→ 0.1 × 700 = 5 × recoil velocity of gun

→ 1/10 × 700 = 5 × recoil velocity of the gun

→ 70 = 5 × recoil velocity of the gun

→ 70 ÷ 5 = recoil velocity of the gun

→ 14 = recoil velocity of the gun

Therefore, Recoil veloticy of the gun = - 14 m/s

[Here we have put (-) sign because the recoil velocity is always negative as it moves in the opposite direction of the fired bullet.]