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[QUOTE=Brock Poling]
So if I stand on the front of a train moving at the speed of light and turn my flashlight on... what happens?    [/QUOTE]

Good question. It is a similar thought experiment that Einstein did to come up with his "special theory of relativity".

The answer is, from your point of veiw nothing unusual would happen. The speed of light remains constant, no matter what speed the source is traveling. Einsteins second postulate.

[QUOTE=Marc] The answer is, from your point of veiw nothing unusual would happen. The speed of light remains constant, no matter what speed the source is traveling. Einsteins second postulate.[/QUOTE]

Actually Marc, you would have to turn your head and look backward to see the waves or particles radiating away from behind you. That is because as you are moving 1 unit of distance, the wave is moving outward at an angle the same distance, but you will be past it before it travels the same distance in the same plane as you. It becomes the hypotenuse of a triangle so-to-speak. The light in front of you would not move past you, so it would not project onto anything in front of you. Because it is moving at the same speed as you, it never gets ahead of you.

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[QUOTE=Don Williams] [QUOTE=Marc] The answer is, from your point of veiw nothing unusual would happen. The speed of light remains constant, no matter what speed the source is traveling. Einsteins second postulate.[/QUOTE]

Actually Marc, you would have to turn your head and look backward to see the waves or particles radiating away from behind you. That is because as you are moving 1 unit of distance, the wave is moving outward at an angle the same distance, but you will be past it before it travels the same distance in the same plane as you. It becomes the hypotenuse of a triangle so-to-speak. The light in front of you would not move past you, so it would not project onto anything in front of you. Because it is moving at the same speed as you, it never gets ahead of you.[/QUOTE]

Don, Einstein's second postulate is very powerful and not intuitive. The flashlight would behave perfectly normal to an observer in the moving train (rocket, whatever).

It's very different than sound waves, for light there is no analog to the medium of propogation (air for sound).

Do you mean to tell me that the aether does not compress and then rarify when you flip on the high beams?   No Santa either, I suppose...

[QUOTE=Marc]Don, Einstein's second postulate is very powerful and not intuitive. The flashlight would behave perfectly normal to an observer in the moving train (rocket, whatever).

It's very different than sound waves, for light there is no analog to the medium of propogation (air for sound).[/QUOTE]

Einstein was wrong.

_________________
"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

I'm with Marc. At least that's what I've been taught all my life and it is what Einstein said. Everything else follows the rules of compression/rarefaction if you're moving, but not light. It is constant even if the source is moving at the speed of light. Don could be right, though, I can't prove it either way.

Ron

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OLD MAN formerly (and formally) known as:

Ron Wisdom

Somewhere in the middle of Arkansas......