Concept explainers
Suppose the object in Problem 70 had an initial velocity in the horizontal direction equal to the terminal speed, vx0 = mg/b. Show that the horizontal distance it can go is limited to xmax = mvx0/b, and find an expression for its trajectory (y as a function of x).
70. Moving through a liquid, an object of mass m experiences a resistive drag force proportional to its velocity, Fdrag = −bv, where b is a constant, (a) Find an expression for the object’s speed as a function of time, when it starts from rest and falls vertically through the liquid, (b) Show that it reaches a terminal velocity mg/b.
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