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Observer S notes that two colored lights, separated by 2400m, occur at positions on the +x-axis of his reference frame. A blue flash occurs first, followed after 5.00μs by a red flash. The red flash is farther away from his origin than the blue. Another observer, R, obtains exactly the same differences in time and position, but declares that the red flash occurred FIRST.

a) What is the relative speed of R, with respect to S, and in what direction

(+x or –x)

b) Calculate which flash occurred closer to the origin of R.

If anyone could get me started I would appreciate it.

moondog

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# Homework Help: Special Relativity problem

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