According to clocks on the ground (system S), streetlights A and B (situated 4 km apart) were both turned on at precisely 8:00 PM. Which one went on first according to an observer on a train (system S'), which moves from A towards B at 3/5 the speed of light? How much later (in seconds) did the other light go on? [Note: As always in relativity, we are talking here about what S'observed, after correcting for the time it took the light to reach her, not what she actually saw (which would depend on where she was located on the train)]

According to clocks on the ground (system S), streetlights A and B (situated 4 km apart) were both turned on at precisely 8:00 PM. Which one went on first according to an observer on a train (system S'), which moves from A towards B at 3/5 the speed of light? How much later (in seconds) did the other light go on? [Note: As always in relativity, we are talking here about what S'observed, after correcting for the time it took the light to reach her, not what she actually saw (which would depend on where she was located on the train)]

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter39: Relativity

Section: Chapter Questions

Problem 77PQ

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