Kinetic Theory and Specific Heat of Gases

Students determine the adiabatic coefficient of air.

The experiment determines the adiabatic exponent of air from the oscillation period of a ball that caps and seals a gas volume in a glass tube. The oscillation of the ball around the equilibrium position causes adiabatic changes in the state of the gas. In the equilibrium position, the force of gravity and the opposing force resulting from the pressure of the enclosed gas are equal.

A deflection from the equilibrium position by Δx causes the pressure to change by ∆p, the cross section of the riser tube, which returns the ball to the equilibrium position.