Question

what Is change in internal energy of a system ,if 20joule of heat is supplied to it and 25joule of work is done by it
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Answer 1

Answer:

Since, work is done on the system so the value of W will be positive as energy is provided to the system. So, W=10J. 

Also heat provided is 50J which means q is also positive and q=50J.

So, using first law of thermodynamics i.e,

change in internal energy = work done + heat provided

=>ΔU=q+W

=>ΔU=20J+25J=45J 

Hence, answer is option A.

Explanation:

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