Imagine you do 4.18 j of work on a system adiabatically, that is to say, without letting it exchange any thermal energy with its surroundings. how much heat, in calories, would you have to put into the system to get the same δe, if no mechanical work was done on or by the system at all?

-4.18 J

Explanation:

Given

System is adiabatic i.e. no heat is added and removed therefore

i.e.

Now to get same change in internal Energy heat added provided mechanical work  is zero

i.e. 4.18 J of heat is removed from system                                            

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