Задача 10727.

The spacecraft is approaching the Earth at a speed of V=0.8c (c is the speed of light in vacuum). The cosmonaut´s understudy, remaining on Earth, slowly turns the meter rod from position 1, perpendicular to the direction of motion, to position 2, parallel to this direction. Find the length of this rod from the point of view of the astronaut on the spaceship.

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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