Question

You and your friend are going bungee jumping! You wait directly below them with a camera. When they leap from the bridge they begin to let out a yell of excitement (or possibly fear) that sounds like the musical note G (392 Hz) as they fall towards you and E (330 Hz) as they bounce back away from you. They continue to yell as they bounce up and down in simple harmonic motion. You notice the pitch of their yell changes as they move toward and away from you. The time in between the highest pitch and lowest pitch is 10 seconds. What is the amplitude of their simple harmonic motion?

Answer 1

When the source will be at the mean position and go towards the observer, the highest pitch will be observed and when the source will be at the mean position and go away from the observer, the lowest pitch will be observed. So, the period will be:

Using the Doppler Effect,

When the source approaches the observer:

When the source moves away from the observer:

By dividing the equations, we get: