A friend speeds by you in her spacecraft at a speed of
Chapter 26, Problem 9(choose chapter or problem)
A friend speeds by you in her spacecraft at a speed of 0.720c. It is measured in your frame to be 4.80 m long and 1.35 m high. (a) What will be its length and height at rest? (b) How many seconds elapsed on your friends watch when 20.0 s passed on yours? (c) How fast did you appear to be traveling according to your friend? (d) How many seconds elapsed on your watch when she saw 20.0 s pass on hers?
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