Wave Properties│Please Help!

Question

The note A above middle C on a piano emits a sound wave with a wavelength of 0.77 meters. What is the frequency of the wave? Use 340 m/s as the speed of the sound wave. What is the period of the sound wave?

Answer 1

All sound waves, regardless of their tone, will travel at the same speed in the same room (the speed of sound actually depends on the medium, or the material, through which it travels). The equation that governs this relationship is

speed = wavelength x frequency

Given:

1. the speed of sound = 340 m/s
2. the wavelength of the wave is 0.77 m

We can rearrange the equation to solve for frequency by dividing both sides by wavelength:

1. frequency = speed / wavelength

The frequency is therefore (340 m/s) / (0.77 m) = 441 waves per second

The unit of "waves per second" is given a special name: Hertz ("Hz"), so the answer is 441 Hz.