Question

A
180-Hz
sound travels through pure helium. The wavelength of the sound is measured to be
5.59 m.
What is the speed of sound in helium?

Answer 1

If we know the frequency of the sound wave, f, as well as its wavelength, λ, then the speed of sound, V_s , is determined by

$${{V}_{s}}=f\cdot \lambda$$

Substituting the given values f=180 Hz and λ=5.59 m, we get the speed of sound in helium

$${{V}_{s}}=180\text{ Hz}\cdot 5.59\text{ m=1006}\text{.2}\,\text{m/s}$$

Answer: the speed of sound in helium is 1006.2 m/s.