The Doppler Effect

Galileos and Einsteins, Thursday:

I am home with my son who is sick.  Please look in the Waves folder for lecture slides on The Doppler Effect, and fill in the notes on "Notes to go with Doppler Effect."  You should also review these images and animations below.

Imagine each of these dots is bobbing up and down on the surface of water, creating waves.

The dot on the left is does not move side to side as it bobs.  The dot on the right moves right.

Here's another view:

Now observe what happens to the frequency in front of the source vs. behind the source.

A similar effect can happen with sounds waves:

In the beginning the engine of the car is making sound, but the car is stationary.  Any observer would head the same pitch (frequency) sound.  Once the car starts moving to the left, the sounds waves to the left (in front of the car) are compressed, and the waves to the right (behind the car) are stretched.  How would an observer in front of the car hear the engine, compared to one behind the car?

Google a video of the Concorde producing a sonic boom.

No homework over vacation...have a nice break!