An experimental determination of the frequencies of free circular plates

Abstract

The paper deals with an experimental determination of the frequency of vibration of circular plates of appreciable thickness. Two sets of observations made (i) with steel discs varying in diameter from 6 to 16 cm. and in thickness from 0.07 to 2.8 cm., and (ii) with discs of various materials all 2 cm. in diameter but varying in thickness, are described. Frequencies were measured at which the discs vibrated with (a) two nodal diameters, (b) one nodal circle. The experimental results are compared with theoretical values. The method may be applied to determine the velocity of sound in materials available only in small quantities.