## Question

A simple pendulum of length *l* and bob mass *m* is displaced from its equilibrium position *O* to a position *P* so that the height of *P* above *O* is *h*. It is then released. What is the tension in the string when the bob passes through the equilibrium position *O*? Neglect friction. V is the velocity of the bob at *O*.

### Solution

P.E. at point *P* = *mgh*. If friction is neglected, the potential is completely converted into kinetic energy when the bob reaches the equilibrium position *O* (see fig). If V is the velocity of the bob at *O*, then

at position *O*, the tension *F* in the string is given by

#### SIMILAR QUESTIONS

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