Question

A revolver of mass 500g fires a bullet of mass 10g with a speed of 100m/a what is the momentum of the bullet

Answer 1

◆ Answer-

a) Initial momentum of system = 0

b) Final momentum of bullet = 1 kgm/s

c) Recoil velocity of revolver = 2 m/s

◆ Explanation-

# Given-

m1 = 10 g = 0.01 kg

m2 = 500 g = 0.5

v1 = 100 m/s

v2 = ?

# Solution-

Initially both revolver and bullet are at rest.

Initial momentum of system is-

p1 = m1u1 + m2u2

p1 = 0.01×0 + 0.5×0

p1 = 0

Final momentum of system is-

p2 = m1v1 + m2v2

p2 = 0.01×100 + 0.5×v2

p2 = 1 + 0.5v2

By law of conservation of momentum-

p1 = p2

0 = 1 + 0.5v2

v2 = -1/0.5

v2 = -2 m/s

Therefore,

a) Initial momentum of system = 0

b) Final momentum of bullet = 1 kgm/s

c) Recoil velocity of revolver = 2 m/s