theoritical experiment on relativity

[drme1981]

Consider a train , its proper length = 375000 km , traveling at a speed of 180000 km/sec (0.6 of speed of light) relative to person (name him B)

Consider a beam of light that travels in the same direction of the train

The train traveler (name him A) will measure the train length = 375000 km , & will measure time required for light beam to travel from the back of the train to the front of the train = 1.25 second (as light travels in a speed of 300000 km/second)

B will measure the length of the train = 300000 km (as length contraction occurs) , & will measure time required for light beam to travel from the back of the train to the front of the train = 1.5625 second (as time dilation occurs for time of A)

B will measure the distance that light beam traveled = 180000 * 1.5625 (the distance that train traveled) + 300000 (the length of train as B measured it) = 281250 + 300000 = 581250 km (B will measure that light travels this distance at 1.5625 second) i.e. B will measure the speed of light = 372000 km/second

Does this prove that light speed is not constant for all observers?

May be I'm intelligent, may be I'm a fool
But I must try , to know what ma I
Even if I'm a fool
I hope you will reply

Thanks

[Loosehead]

factor in the time dilation dear boy!

[mibn2cweus]

Drme1981,
I am not quite grasping the implications of your text. Here is my preliminary assessment:

Santa measured the span of Rudolph�s antlers (one metre) as Rudolph boarded the caboose of the train aka the �Comet�. Santa noticed that Rudolph�s nose was on the blink, emitting a brief pulse of light precisely once every four seconds. Seeing the pulse reflecting off the trains shiny locomotive 2.5 seconds later, Santa deduced the length of the Comet to be half that (1.25 light seconds) or 375000 km long.

Twas the night before X-mass when to Santa�s great surprise he looked up to see Rudolph�s nose blinking away at the tail end of the Comet as it streaked across the sky at a velocity equal to 60% of the speed of light or (180000 km/s).
To Santa�s astonishment the Comet appeared to have shrunk to a mere 300000 km in length.
Santa was no less amazed to find that Rudolph�s nose was now blinking only once every five seconds and that it took the light from Rudolph�s blinking nose 2.5 seconds to be reflected from the locomotive. The reason for this delay is that from Santa�s perspective, the front of the train had advanced (180000 km/s * 2.5 s = ) 450000 km in the time it took the light from Rudolph�s nose to travel the length of and finally overtake the locomotive of the Comet.

continued . . .

[mibn2cweus]

When Rudolph returned from his trip aboard the Comet he reported to Santa that, based on known distances from Earth and the trains clock, he had measured the Comet�s velocity to be an even more astonishing 225000 km/s, that he had measured no variation in the length of the train or the velocity of light when they were measured using the one meter breadth of his antlers as a reference and that he had experienced no changes in the frequency at which his nose blinked throughout the trip. Even though Rudolph was quite certain that he got back in plenty of time to prepare for X-mass deliveries, Santa was frantic knowing that due to the lateness of Rudolph�s return, in fact they would have to exceed the velocity of light to get the presents delivered to all the good little girls and boys in time. (For some reason upon returning, the trains clock required a forward adjustment to agree with the station clock).

So what am I missing in your conjecture?