## Question

A simple pendulum is moving simple harmonically with a period of 6 s between two extreme position B and C about a point O. if the angular distance between B and C is 10 cm, how long will the pendulum take to move from position C to a position D exactly midway between O and C.

### Solution

1.0 s

Given time period T = 6 *s*

Let the displacement of the pendulum be given by

let us suppose that at *t* = 0, the pendulum is at *C*, i.e., at *t* = 0, *x* = *A*, so that

Thus the motion of the pendulum is given by

The value of *t* for which *x* = 2.5 cm is given by

2.5 = 5 cos ωt

#### SIMILAR QUESTIONS

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