A 1300kg car A stikes a parked 1200kg car B. Car B slides 2m after impact. The coefficient of friction between B's tires and the road is u=0.8. The coefficient of restitution is e=0.4. What is the velocity of A just before impact?(adsbygoogle = window.adsbygoogle || []).push({});

I have the equations:

mA*vA + mB*vB = mAvA' + mBvB'

e = (vB' - vA')/(vA - vB)

The initial velocity for B is zero so I still have three variables and only two equations. What other equation do I need to solve this problem? I thought about conservation of energy, but how does friction play into this?

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# Homework Help: Collision Problem

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