1.) the lowest- pitch sounds humans can generally hear have a frequency of roughly 0.02khz. what is the approximate wavelength of these sound waves if their wave speed is 340 m/s? 2.) what is the speed of a sound wave that has a wavelength of 2,000 mm and a frequency 170.5 hz? 3.) what is the frequency of a wave if it has a velocity of 25m/s and a wavelength of 2.5 meters?

1) The frequency of the sound is

while the speed of sound is 

So we can use the relationship between wavelength, speed and frequency of a wave to find the wavelength corresponding to this sound:


2) The wavelength in this case is

while the frequency of the wave is 

So we can use the same relationship we used in part 1) to find the speed of the sound wave:


3) The velocity of the wave is

while its wavelength is

therefore we can find its frequency by using the usual relationship: