Given,
The frequency of the sound, f=40 Hz
The speed of the sound in the air, c=340 m/s
The speed of a wave in a medium is given by the product of the frequency and the wavelength of the wave.
Thus the speed of the sound with the given frequency is calculated using the formula,
Where λ is the wavelength of the wave.
On rearranging the above equation,
On substituting the known values,
Thus the length of the wave or the wavelength of the given wave is 8.5 m