Define Heat Capacity Ratio?

To find C_p/C_v of a gas, one occasionally uses the following method. A certain amount of gas with preliminary temperature T₀ pressure P₀ and volume V₀ is heated by a current flowing by a platinum wire for a time t. The experiment is done twice first at a constant volume with the pressure changing P₀ to P₁ from to and then at a constant pressure P₀ with the volume changing from V₀ to V_1. The time t is the similar in both experiments. Find the ratio C_p/C_v (the gas may be considered ideal).