The velocity of longitudinal sound waves in liquid 4Heat temperatures below 0.6 K is 2.383 × 104 cm s–1. There are no transverse sound waves in the liquid. The density is 0.145gcm-3.
(a) Calculate the Debye temperature
(b) Calculate the heat capacity per gram on the Debye theory and compare with the experimental value Cv = 0.0204 × T3, in Jg-1 K-1. The T3 dependence of the experimental value suggests that phonons are the most important excitations in liquid 4He below 0.6 K. note the experimental value has been expressed per gram of liquid. The experiments values have been expressed per gram of liquid.