AIPMT 2010 Physics and Chemistry Paper

According to first law of thermodynamics ∆Q=∆U+∆W.....(i)
where,
∆Q= Heat supplied to the system
∆u= Increase in internal energy of the system
∆W= Work done by the system
For an adiabatic process
∆Q=0
From equation (i), we get
∆u=−∆W
For an isothermal process
∆u=0