Relativity Questions: Help Required! (1 Viewer)

[HeavenlyAnarchy]

Ok, so here goes the problem.

This question is apart of an assignment i was given on "Special Relativity".

In one of Einstein's famous thought experiments, a passenger travelling on a train passes through a station at 60% of the speed of light. According to the passenger, the length of the train carriage is 22m from front to rear.

1. A light in the train carriage is switched on. Compare the velocity of the light beam as seen by the passenger on the train and a rail worker standing on the station platform.
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1. Calculate the length of the carriage as observed by the rail worker on the station platform.​

The problem i am facing is that i do not believe i have enough information.
I do not know where the train is, past, approaching or at my current position when the light is turned on. I am ASSUMING also that the passenger is standing right by the light when it is on, because i assume that if the passenger is somewhere else on the train, let's say 10m away from it, and the rail worker is 10m away from light when turned on (yes close to the platform) wouldn't the light reach them at the same time because the time it would take to reach them both, the train is basically still at THAT MOMENT. So if it didn't reach them at the same time if they were the same distance away, wouldn't that violate the principle of relativity? Because that would infer that the speed of light is not INFACT constant at all.

Hopefully you can see my problem, help would be appreciated.

Thanks,
Dwayne​

 

[Lucid Scintilla]

In one of Einstein's famous thought experiments, a passenger travelling on a train passes through a station at 60% of the speed of light. According to the passenger, the length of the train carriage is 22m from front to rear.

1. A light in the train carriage is switched on. Compare the velocity of the light beam as seen by the passenger on the train and a rail worker standing on the station platform.
2. Calculate the length of the carriage as observed by the rail worker on the station platform.

The problem I am facing is that I do not believe I have enough information.

I do not know where the train is, past, approaching or at my current position when the light is turned on. I am assuming also that the passenger is standing right by the light when it is on, because I assume that if the passenger is somewhere else on the train, let's say 10m away from it, and the rail worker is 10m away from light when turned on (yes close to the platform), wouldn't the light reach them at the same time because the time it would take to reach them both, the train is basically still at that moment? So, if it didn't reach them at the same time if they were the same distance away, wouldn't that violate the principle of relativity? Because that would infer that the speed of light is not, in fact, constant at all.​

Grammar, please.

1. The light beam's velocity is constant for both the passenger and the worker, otherwise it would violate the principle of relativity. If you're worrying about simultaneity, then that's different.
2. Using length contraction formula, L_v = L₀ x Lorentz correction factor, where L_v is the length the observer sees, and L₀ is the proper length (the length of the train as measured by observers at rest with respect to it).

L_v = (22)(0.8) = 17.6 m
The train's apparent length has contracted.​

 

[twilight1412]

just a quick side note to help you remember
proper time is always with improper distance
and
proper distance is always with improper time