Why work done in constant volume process is zero ?

The work done in an ischoric process is

Statement-1: For a gaseous system C_(p) is always greater than C_(v) Statement-2: Work done by a gas at constant volume is zero.

Why is the work done in isobaric process not zero always?

Work done in given cyclic process is

Can the work done during a cyclic process be zero?

Work Done By A Constant Force

The work done in which of the following processes is zero

The work done in adiabatic process is given by