If a monkey of 18 kg jumps on a running truck of 1000 kg,then what is the kinetic energy of the truck after the monkey jumped?

What do you think it is and how would you arrive at that figure?

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What do you think it is and how would you arrive at that figure?Site rules about homework require you to provide an answer and what work you have done.I have tried E=½mv²... but it is not working..

"Help me calculate the energy". We'll help but not do. Show us your thoughts and what you have done.

https://www.easycalculation.com/physics/classical-physics/kinetic-energy.php

I have tried E=½mv²... but it is not working..

Show us your calculations, and why you think "it is not working." You don't mention whether the speed of the truck is constant. The calculation of 1/2 mv^2 should work, as long as you use the correct values of m and v. This may be a bit of trick question - note that it asks for the KE of the truck, not the KE of the truck plus monkey.