Morin Problem 3.69

Physics · mechanics

Problem

A force Fθ\theta = 2mr˙θ\theta˙ Consider a particle that feels an angular force only, of the form Fθ\theta = 2mr˙θ\theta˙. Show that r = Aeθ\theta + Be−θ^{-\theta}, where A and B are constants of integration, determined by the initial conditions. (This force is actually a physical one. If you put a bead on a stick and swing the stick around one end at a constant rate, then the normal force from the stick happens to be 2mr˙θ\theta˙.26^{26})

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