A meterstick is at rest in an inertial frame S2.If S2 moves with a speed of 0.8 c with respect to a rest frame S1, find the length of the meterstick as measured in frame S1 according to classical physics. Answer in units of m.
According to "classical" (pre-1905) physics, the length will be the same in both coordinate systems. They must mean according to relativistic physics, which results in the correct answer,
L' = L*sqrt[1 - (v/c)^2]
The meter stick will appear shorter, but the formaula above only applies if the stick is aligned with the direction of motion.
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