Can somone simplify the definition of the dopler effect for me?

Question

i know it has something to do with the sound of sound (if that makes any sense!) as the sourse of the sound moves away from you!

Answer 1

Go to http://en.wikipedia.org/wiki/Doppler_eff... .  It has an explenation regarding baseballs under analysis hope it works for you.

Answer 2

http://www.google.com/search?hl=en&clien...

Answer 3

as something is travelling towards you making a noise, the sound frequency is compressed (the frequency cycles are pushed together a bit by the velocity) therefore the frequency of the sound sounds higher than it actually is.

As it passes you it sounds about the right frequency... as it moves away the frequency is stretched a bit by the velocity that it is moving away... therefore the frequency appears to get lower.

Thats how it was explained in simple terms to me many years ago.

Answer 4

It has to do with sound, but also anything else that is traveling through a medium (light, radio waves, etc).  However, sound is the easiest to understand because its the one we can relate to the most.

When an ambulance is approaching you with its lights on, you hear a certain pitch.  Then, as soon as it passes you, the pitch changes to something a little lower.  

This is because when its coming at you, the sound waves are pushed together a little bit.  The speed of sound is much faster than the ambulance; however, the speed of the ambulance adds a little bit of energy to the waves.  But then, when it passes you, that speed of the ambulance is taken away from the speed of the siren, resulting in a lower pitch than reality.

The actual pitch of the siren is half-way between the higher pitch when approaching, and the lower pitch when going away.

Likewise, the same thing happens with light.  If I am coming at you in my spaceship at a very very high speed, and I turn on my light, you will see my light as being more blue than it actually is, because its frequency is increased by my speed.  However, if I'm going away from you and I shine my light at you, the light will look more red for the same reason.  Therefore, these effects are called "blueshifts" and "redshifts".