A gun of mass 500g fires a bullet of mass 10g with a speed of 100m/s.
Find:
(a) Initial momentum of ' gun + bullet ' .
(b) Momentum gained by the bullet after firing.
(c) Recoil velocity of the gun
Information provided in the question is as follows:
As initially both the gun and the bullet are at rest so the velocity of both bullet and gun is 0.
Therefore, the initial momentum of gun and bullet, pi = Mvi+mvi' = 0
Momentum gained by the bullet after firing, p = mv = 0.01×100 = 1 kg m s-1
Let the recoil velocity of the gun be V.
From conservation of momentum,
Final momentum of the system = initial momentum of the system
MV +mv = 0
⇒0.5×V = -1
⇒V = - 1/0.5 = -2 m/s
| Mass of the gun, M | 500 g = 0.5 kg |
| Mass of the bullet, m | 10 g = 0.01 kg |
| Velocity of the bullet, v | 100 m/s |
As initially both the gun and the bullet are at rest so the velocity of both bullet and gun is 0.
Therefore, the initial momentum of gun and bullet, pi = Mvi+mvi' = 0
Momentum gained by the bullet after firing, p = mv = 0.01×100 = 1 kg m s-1
Let the recoil velocity of the gun be V.
From conservation of momentum,
Final momentum of the system = initial momentum of the system
MV +mv = 0
⇒0.5×V = -1
⇒V = - 1/0.5 = -2 m/s