What is the recoil speed of the rifle?

1. The problem statement, all variables and given/known data
Kim holds a 2.0 kg air rifle loosely and fires a bullet of a mass 1.0 g. The muzzle velocity of the bullet is 150 m/s. What is the recoil speed of the rifle?


2. Relevant equations
p=mv


3. The attempt at a solution
p=(150)(.01) 15=2v
p=15 7.5=v
 

rock.freak667

Homework Helper
6,232
27
Re: Momentum

Looks correct. Just note that it is -7.5m/s
 

Borek

Mentor
27,852
2,424
Re: Momentum

No, it is not OK. 1.0g is not 0.01kg.

Even assuming it is, 150*0.01 is not 15.
 
Re: Momentum

I apologize wasn't what i had on my paper in a bit of rush to see if i was understanding the equation. You are absolutely right 1 g is .001kg and it multiplied by 150 is 1.5, but besides careless errors i just want 2 know am i on the right track
 

Borek

Mentor
27,852
2,424
Re: Momentum

General approach seems to be OK :smile:
 

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