Doppler Effect
St. Mary's Physics Online

D. Doppler Effect – variation in the observed frequency of a wave when there is relative motion between the source of the wave and the receiver

Doppler Effect V = 14 m/s
(B. Barrett)

Doppler Effect V = 18 m/s
(B. Barrett)

Stationary Ambulance

Which way is this ambulance moving?

To the left

The Doppler Effect II
Colorado University

"A "sonic boom"

is heard when a

plane exceeds

the speed of sound. "

Did you know .....

The crack of a whip is the sound of the
tip breaking the speed of sound.

"Which way is the

source of this wave

moving?"

"To the right, where

the frequency

is higher"

Radar Guns & Waves
St. Mary's HS Physics