Question

What will be the wavelength of ultrasonic wave in air if the frequency of the wave is 20khz

Answer 1

see speed is 340 let's take it as its speed is equal to speed of sound

Answer 2

speed of sound = V

wavelength = λ

frequency = v

the time period of a wave is represented by = T = 1/v

In time T, a distance of wave length v is covered

so the speed of sound = V = λ/T

or V = λv