in the direction in which the train is traveling. Compare the speed of the light beam relative to the ground when the train is at rest and when it is in motion. How does the behavior of the light beam differ from the behavior of the bullet in Exercise 3? (my previous question)
2006-11-20 09:08:02 · 3 answers · asked by lostprophetslove 1 in Science & Mathematics ➔ Physics
For a bullet, one can add the speed of the bullet to the speed of the train making it a cumulative velocity.
Not the same for light. The speed of light is constant no matter the velocity of the observer. The rider on the train would observe the beem going away from him at 3x10^8 mps and a person on the ground would observe the light traveling away at 3 x 10^8 mps.
2006-11-20 10:26:38 · answer #1 · answered by Paul O 3 · 1⤊ 0⤋
Light does not have mass and is constant to all observers. So to you the light would seem to move away at the speed of light. In reference to the ground, light would be moving faster than the speed of light. This is different that a bullet which does have mass. The bullet is going to be fired with the same respect to the ground as it would if you were on the ground, but will appear slower on the back of the train.
2006-11-20 09:13:48 · answer #2 · answered by Chris J 6 · 0⤊ 0⤋
The light beam would seem to be moving slower when the train is moving. The light moves away at the speed of light when the train is not moving; when the train starts to move, the light moves away at the speed of light minus the speed of the train (the speed of light is a constant that cannot be broken, hence the light cannot move 'faster than the speed of light', unless the laws of physics have been rewritten)
2006-11-20 09:19:40 · answer #3 · answered by Star G 4 · 2⤊ 0⤋