(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A man holding a gun ((mass of man)+(mass of gun)+(mass of bullet)=60kg)) skates on frictionless ice at an initial speed of +2 m/s and fires a 100 gram bullet with a speed of +500 m/s from the gun.

a) What is the speed of the man after firing the gun? (be sure to include +/- direction)

b) What is the initial total energy of the man-gun-bullet system (before the bullet is fired)? What is the final total energy of the man-gun-bullet system (just after the bullet is fired)?

c)is this an example of an elastic, inelastic, or perfectly inelastic collision, and why? I don't understand this concept very well.

2. Relevant equations

Pi=Pf

M1V1i + M2V2i = M1V1f + M2V2f

Total KE (before)= .5MV^2

Total KE (after)= .5M1V1^2 + .5M2V2^2

3. The attempt at a solution

I think this is correct, but I'm not completely sure.

I'm not sure if its elastic or inelastic, I have trouble understanding that stuff.

60*2=59.9*v+.1*500

v=1.17 m/s

energy before is

.5*60*4 J

120 J

after

.5*.1*500^2+.5*59.9*1.17^2 J

12541 J

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# Homework Help: Uncertainty about answer for Conservation of Momentum Problem

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