(adsbygoogle = window.adsbygoogle || []).push({}); A rocket of length l0 measured in its rest frame S0 is travelling away from an observer in a frame S with a velocity u = 2/3 c. A light pulse is emitted from the nose of the rocket (x' = l0) at t0 = 0 and travels to the tail (x' = 0) where it is reflected back to the nose.

In S0, when does the light pulse reach the tail and when does it get back to the nose?

How long does the light pulse take to travel from nose to tail and back again

as determined by the observer in S?

Here is my solution

the time the pulse takes to travel from nose to tail is l0/c.

The time when it get back to the nose is t=2*l0/c.

For the second part, the total time it takes is gamma*2*l0/c where gamma=1/(1-v^2/c^2)^1/2 and v=2/3c

I think my solution is too simple, have I misunderstood the question ? Could somebody help me check it please. Thanks

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# Homework Help: Could somebody help me check the solution please. (special relativity)

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