How Does Collision Affect Kinetic Energy in Fish?

[stupif]

1. A big fish with its mouth wide open is moving at 2.0m/s towards a school of small fish each of mass 300g. the small fish enter the wide mouth of the big one with a velocity of 5m/s to the opposite durection at the rate of 20fish per min. the big one is motionless after 13min : the big one is able to finish collecting all the available small ones. the total collection time is 13 mins. Find the loss in kinetic energy due to the impact



2. i found out the mass of big fish= 195kg
but how to find the loss in kinetic energy due to the impact?
the answer is 1365J
help me...please
thank you

The Attempt at a Solution

 

[gneill]

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