According to the first law of thermodynamics, `DeltaU=q+w`. Write down the form of this equation for the following process: (i) cyclic process (ii) adiabatic process (iii) isothermal expansion of an ideal gas (iv) process occurring in an isolated system.

Explanation

(iv) An isolated systemm does not exchange energy or matter with its surroundings. So, for a process occuring in an isolated system, q=0 and w=0. therefore, `DeltaU=q+w` or, `DeltaU=0+0` or, `DeltaU=0`.