- #1
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This is a problem I have thought about for a long time without any progress. Please give me a hint.
Cars B and C are at rest with their brakes off. Car A plows into B at high speed, pushing B into C. If the collisions are completely inelastic, what fraction of the initial energy is dissipated in car C? Initially the cars are identical.
[tex]p_{i}=p_{f}[/tex]
The momentum is conserved and since it is a completely inelastic collision the cars are stuck to each other with velocity v, different from the initial velocity v0. [tex]mv_{0}=3mv[/tex] and [tex]v=\frac{v_{0}}{3}[/tex] and for car 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?
Homework Statement
Cars B and C are at rest with their brakes off. Car A plows into B at high speed, pushing B into C. If the collisions are completely inelastic, what fraction of the initial energy is dissipated in car C? Initially the cars are identical.
Homework Equations
[tex]p_{i}=p_{f}[/tex]
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 velocity v, different from the initial velocity v0. [tex]mv_{0}=3mv[/tex] and [tex]v=\frac{v_{0}}{3}[/tex] and for car 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?