Question

The first resonant length of a closed air column occurs when the length is 16 cm. 

a) What is the wavelength of the sound? 

b) If the frequency of the source is 512 Hz, what is the speed of sound?

Answer 1

a) the wavelength of the sound is

$$\lambda=4L=64\text{ cm}.$$

b) The speed of sound is

$$c=\lambda f=64·512=328\text{ m/s}.$$