Rifle recoil speed homework

[physicsjessic]

Homework Statement

A rifle has amass of 4.5 kg and it fires a bullet of mass 10 g at a muzzle spped of 820m/s what is the final recoil speed of the rifle as the bullet leaves the gun barrel?

Homework Equations

conservation laws

The Attempt at a Solution

4.5v=1000*820
v=1.8*10^5

 

[Chewy0087]

What? 0.0 The mass of the bullet is 10 grams, not 1000 kg. =D

Be consistent with your units, but your method is sound, I suggest converting your grams in kilograms.