Question

A pendulum with a bob of mass m is oscillating on either side from its resting position A between the extremes B and C at a vertical height h above A. What is the kinetic energy K and potential energy U when the pendulum is at positions (i) A, (ii) B and (iii) C?

April 24, 2024

Answer

(i) For position A,

The pendulum has the maximum kinetic energy and potential energy is zero at its resting position.

So, K = mgh and U = 0

(ii) For position B,

The kinetic energy starts decreasing and the potential energy starts increasing.

So, K = 0 and U = mgh

(iii) At position C,

Kinetic energy K = 0 and potential energy U = mgh.

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