Question

5. A bullet of mass 0.01 kg is fired from a gun
weighing 5.0 kg. If the initial speed of the bullet
is 250 m/sec, calculate the speed with which
the gun recoils -
​

Answer 1

Given :-

• Mass of bullet = 0.01 kg
• Weight of gun = 5 kg
• Initial speed = 250 m/s

To find :-

• Recoil speed of gun

Solution :-

Let the recoil velocity of the gun be v

Here , according to the question the momentum of bullet is transferred to the momentum of gun .

Now , in other form

p(gᵤₙ) = - p(bᵤₗₗₑₜ)

Substituting momentum = mass × velocity

5 × v = - 0.01 × 250

5v = - 1/100 × 250

5v = - 5/2

10v = - 5

- 5/10 = v

- 1/2 = v

v = - 0.5 m/s

Hence , recoil speed of velocity = - 0.5 m/s