Задача 11105.

In a horizontal smooth pipe there is an annular loop of radius r, located in a vertical plane. With what minimum speed should a thin flexible rope of length l> 2pr move in the horizontal section of the pipe to pass through the loop? Consider the radius of the loop r much greater than the radii of the pipe and rope.

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