The relationship between frequency, wavelength and speed of a wave is given by: [tex]f= \frac{v}{\lambda} [/tex] where f is the frequency v is the speed of the wave [tex]\lambda[/tex] is the wavelength
The bat sound has a wavelength of [tex]\lambda=3.7 mm=3.7 \cdot 10^{-3} m[/tex] while the speed of the wave is just the speed of sound in air: [tex]v=343 m/s[/tex] Therefore, the frequency of the bat sound is [tex]f= \frac{v}{\lambda}= \frac{343 m/s}{3.7 \cdot 10^{-3}m}=9.27 \cdot 10^4 Hz [/tex]
