Car A hits car B (initially at rest and of equal mass) from behind while going 15 m/s Immediately after the collision, car B moves forward at 10 m/s and car A is at rest. What fraction of the initial kinetic energy is lost in the collision?

Given :

Initial speed of car A is 15 m/s and initial speed of car B is zero.

Final speed of car A is zero and final speed of car B is 10 m/s.

To Find :

What fraction of the initial kinetic energy is lost in the collision.

Solution :

Initial kinetic energy is :

Final kinetic energy is :

Now, fraction of initial kinetic energy loss is :

Therefore, fraction of initial kinetic energy loss in the collision is 1.25 .

im not to sure what it is

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