MEASUREMENT OF THE VELOCITY OF SOUND IN LOW TEMPERATURE LIQUIDS AT ULTRASONIC FREQUENCIES

Abstract

An ultrasonic interferometer apparatus has been developed for the measurement of the velocity of sound in low temperature liquids. The method follows in general the conventional manner of producing sound waves in a liquid, i.e., by the vibrations of a piezoelectric quartz plate driven at a high frequency. The velocity of sound in liquid oxygen and hydrogen at an ultrasonic frequency of 427 kilocycles per sec. was found to be:—oxygen, 912 metres per sec. (temp., − 182.9 °C); hydrogen, 1127 metres per sec. (temp., − 252.7 °C).