This is a problem I have thought about for a long time without any progress. Please give me a hint.(adsbygoogle = window.adsbygoogle || []).push({});

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

CarsBandCare at rest with their brakes off. CarAplows intoBat high speed, pushingBintoC. If the collisions are completely inelastic, what fraction of the initial energy is dissipated in carC? Initially the cars are identical.

2. Relevant equations

[tex]p_{i}=p_{f}[/tex]

3. The attempt at a solution

The momentum is conserved and since it is a completely inelastic collision the cars are stuck to each other with velocityv, different from the initial velocityv. [tex]mv_{0}=3mv[/tex] and [tex]v=\frac{v_{0}}{3}[/tex] and for car_{0}C

[tex]\frac{E_{C}}{E_{0}}=\frac{(v_{0}/3)^{2}}{v_{0}^{2}}=\frac{1}{9}.[/tex] Unfortunately the answer in my answer sheet is 1/6. What is wrong?

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# Homework Help: Completely inelastic collision

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