Question
State First law of thermodynamics.
✓
Answer
According to first law of thermodynamics when some quantity of heat (dQ) is supplied to a system capable of doing external work, then quantity of heat absorbed by the system (dQ) is equal to sum of increase in internal energy of system (dU) due to rise in temperature and external work done by system (dW) in expansion i.e.
dQ = dU + dW
dQ = dU + dW
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