Question 1198899
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The initial kinetic energy (KE) was {{{(mv^2)/2}}} = {{{(2000*5^2)/2}}} = 25000 joules.


5000 joules was spent for slowing down.


The resting KE is the difference  25000 - 5000 = 20000 joules.    <U>ANSWER</U>
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Solved, with full explanations.