Energy Lost during elastic collision.

[orientor]

Homework Statement

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True or False:[/B]
For a completely elastic collision of two isolated masses the energy lost is
½μν_r²
Where μ is the reduced mass of the system and ν_r is the magnitude of relative velocity between the two particles.

Homework Equations

The Attempt at a Solution

Elastic collision is defined as collision in which no energy is lost. So the answer should be false. But the answer in the answer key is true. So what is the error?

 

[kuruman]

The error is in the answer key. The statement is True for an inelastic collision in which the masses stick together.

 

[orientor]

Thanks.