Doppler Effect

Question

What is Doppler Effect?

This Image taken from

www.mynamesnotmommy.com 

Definition

• The change in frequency of a  wave (or other periodic event) for an observer moving relative to its source.

History• First explained in 1842 by Christian Doppler.

By wiki

Stages

• Sound source and Listener are static.• Sound source Moves toward a stationary Listener.• Sounding source moves away from a stationery Listener• Listener Moves toward a stationery source.• Listener Moves away from the stationery source.• Sound source and Listener both going away.

Resting sound source

sourceat rest

observer at rest

Frequency fs Frequency fo

s of f=

Sound source moving toward observer

source observer at rest

Sound source moving away from observer

sourceobserver at rest

Frequency fsFrequency fo

Listener Moves toward a stationery source

This expression indicates that the frequency of sound as heard by the listener is

decreased and he will detect a lower pitch of sound.

Listener Moves away from the stationery source.

• The frequency of sound is decreased frequently and he will

detect a lower pitch of sound.

APPLICATION

• Radar Gun.• Doppler Radar.• Sonar waves system.• Geo satellite.• Light.• Sonic Boom.

Thanks

• Thanks for your consideration

Q & A

• Any Question?