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

A bullet of mass 0.0800 kg is fired onto an empty box of mass 0.920 kg initially at rest. Upon hitting the box, the bullet has a speed of V= 900.0 m/s and is oriented horizontally. After hitting the box, the bullet passes through it and emerges with a speed of 1/2V. The box also moves but due to the rough surface it is on, it stops after moving a distance of s. If the coefficient of kinetic friction is 0.500, find s.

2. Relevant equations

W other= ∆E (mechl energy) + ∆E therm

∆E = (K2+U2) - (K1+U1) + f∆x

3. The attempt at a solution

what i did is i used the Wother formula to solve for ∆x.. my answer was .10m.

this is wrong because the choices to the multiple choice question are: A. 3.99m B. 39.1 C. 72.0m D. 99.7 E156m

I think there is more to this problem then using the Wother formula.. do i need to use the conservation of momentum??

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Help! mechanical energy problem

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