A hiker shouts toward a vertical cliff

Question

A hiker shouts toward a vertical cliff 695 m away. The echo is heard 4.00 s later. In air the hiker's voice travels 347.5 m/s.

(a) The wavelength of the sound is 0.724 m. What is its frequency?

____Hz

(b) What is the period of the wave?

_______ms

Answer 1

If c=speed of sound

dx=695 m

dt=4.00 s

l=wavelength of the sound = 0.724 m.

c=dx/dt=173.75m/s

c=l*f

f=c/l

T=1/f