Question

The muzzle velocity of a 50.0g shell leaving a 3.00 kg rifle is 400m/s what is the recoil velocity of the rifle

Answer 1

Here if we consider bullet and gun as a system then we can say that momentum of the system will remain conserved

so we will have

`m_1v_(1i) + m_2v_(2i) = m_1v_(1f) + m_2v_(2f)`

now we know that

`m_1 = 50 g = 0.050 kg`

`m_2 = 3 kg`

`v_(1i) = v_(2i) = 0`

`v_(1f) = 400 m/s`

now we will have

`0.050(0) + 3(0) = 0.050(400) + 3(v)`

`20 + 3v = 0`

`v = - (20)/(3) = - 6.67 m/s`

so gun will recoil with speed 6.67 m/s