Question

Explain the thermodynamics of adiabatic process to obtain adiabatic constant for rigid diatomic molecule of a gas?

Answer 1

An adiabatic process is one in which no heat is transferred to or from the system. The P–V diagram of an adiabatic process is shown in the figure. In this instance, Q equals zero. The system is either completely insulated from the environment or the process proceeds rapidly to prevent any heat exchange. Δ U = −W for an adiabatic transformation.

W is positive when a system expands adiabatically due to the work done by the system, while Δ U is negative as a result of the system's internal energy decreasing.

W is negative when a system is compressed adiabatically, as work is performed on the system, and Δ U is positive. In an adiabatic process, the system's internal energy increases.

PV^γ = C for an adiabatic process, where γ is the ratio of the specific heat at constant pressure to the specific heat at constant volume. γ is equivalent to `c_P/c_V`.

In the case of diatomic gases, the adiabatic ratio, also known as γ, is `7/5` for moderate temperature changes.