Question

Starting at rest a man falls from the surface of earth.

He feels a drag force FD = bv2(t), where b is a constant, and v(t) is his velocity as a function of time. If his mass is m, show that v(t) = A tanh (Bt)

where tanh is the hyperbolic tangent function, and determine the constants A and B

in terms of m, g, and b

Answer #1

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