Question

1st law of thermodynamics?

Answer 1

it states that if an amount of heat dQ is added to a system , a part of it may increase its internal energy dU while the remaining part may be used up as the external work dW done by the system .
i.e. dQ=dU+dW=dU+pdV
where p is the pressure and dV is the change in volume of system.

Answer 2

First law of thermodynamics
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It states that the heat energy given to a system is equal to the sum of the increase in internal energy and the work done by the system
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dQ = dU + dW
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dQ = heat energy
dU = internal energy
dW = work done
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