Задача 10724.

The spacecraft is moving away from the Earth at a speed of V=0.8c (c is the speed of light in vacuum). The astronaut on the ship slowly turns the meter rod from position 1, parallel to the direction of motion, to position 2, perpendicular to this direction. Find the length of the rod from the point of view of an earthly observer.

A detailed solution with a brief note of the condition, formulas and laws used in the solution, the derivation of the calculation formula and the answer.
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