A guy dives from a cliff of height H at an initial speed 0 (for simplicity). During the first phase of his fall, he wraps his arms. During the second phase, he stretches his arms to slow himself down so that his touchdown speed at the water surface is vo. The air drag coefficient during the first phase is k while it is ßk during the second phase. The air drag force is always proportional to the falling speed. At what height the guy should open his arms so that his touchdown speed is vo? Compute the total falling time.

A guy dives from a cliff of height H at an initial speed 0 (for simplicity). During the first phase of his fall, he wraps his arms. During the second phase, he stretches his arms to slow himself down so that his touchdown speed at the water surface is vo. The air drag coefficient during the first phase is k while it is ßk during the second phase. The air drag force is always proportional to the falling speed. At what height the guy should open his arms so that his touchdown speed is vo? Compute the total falling time.

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter5: More Applications Of Newton’s Laws

Section: Chapter Questions

Problem 61P

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