Ruchardt's tube: Ball oscillates in a vertical glass tube on jug.

Ruchardt's tube: Ball oscillates in a vertical glass tube in jug. This apparatus is for determining the ratio C /C . It consists of a 60 cm. precision bore glass tube attached vertically to a 1 gallon glass jug. A steel ball is allowed to fall in the tube. The enclosed volume of air acts as a cushion, and the ball oscillates harmonically. The oscillations are damped by friction inside of the tube. The ratio can be derived using the period of oscillation, mass of ball, cross-sectional area of the tube, volume of the enclosed air, and pressure in the bottle. KINETIC THEORY AND GAS MODELS.