Recent content by A.Brown

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    Train emitting radio signal from tunnel midpoint in special relativity

    Oh, the clocks in S' would read 2 minutes to get to the mid-point + 0.75 minutes for B, and 2 + 3 minutes for the signal to reach A?
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    Train emitting radio signal from tunnel midpoint in special relativity

    Ok, so then solving for Δt' for both expressions, I'm getting 0.75 minutes for the signal to reach B and 3 minutes for the signal to reach A according to the observers in S' who see the tunnel as 2.4 c*min long (making L'/2 = 1.2 c*min)?
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    Train emitting radio signal from tunnel midpoint in special relativity

    Oh, ok, so then for A does that make it L'/2 + 0.6cΔt' = cΔt' making L'/2 = cΔt'-0.6cΔt' because in reaching A, the signal has to travel extra distance as the end of the tunnel rushes away from the emission point?
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    Train emitting radio signal from tunnel midpoint in special relativity

    If the signal is defined as moving in the positive direction, to the right towards B, then isn't the tunnel approaching in a negative x direction? If not, then L'/2 = cΔt'+0.6cΔt' but then I'm not sure how to do the calculation for the signal approaching A, which is receding from the point...
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    Train emitting radio signal from tunnel midpoint in special relativity

    Sorry, I'm still confused. When the signal is emitted: A( []--> )B |--L'/2--|--L'/2--| B appears to be moving towards the signal at 0.6c in S'. When the signal arrives: A( cΔt'--><--0.6cΔt')B Which seems like L'/2 = cΔt'-0.6cΔt' ? What am I missing?
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    Train emitting radio signal from tunnel midpoint in special relativity

    Is L' = cΔt' - 0.6cΔt' for the end B the train is moving towards?
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    Train emitting radio signal from tunnel midpoint in special relativity

    I was afraid of that :) How do I account for that? Can I use γt + (vγt)/c for A and γt - (vγt)/c for B?
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    Train emitting radio signal from tunnel midpoint in special relativity

    Homework Statement A very fast train (system S') travels on a straight track (system S) with speed 0.6c. When it enters a tunnel (at end A), which is 3 c*min long relative to S, observers in S and S' set their clocks to zero. The train will emerge from the tunnel at end B. At the midpoint of...