Question

A pendulum is oscillating on either side of its rest position. The correct statement is :
(a) It has only the kinetic energy at its each position.
(b) It has the maximum kinetic energy at its extreme position.
(c) It has the maximum potential energy at its mean position.
(d) The sum of its kinetic energy and potential energy remains constant throughout the motion.

April 24, 2024

Answer

(d) The sum of its kinetic and potential energy remains constant throughout the motion.

Reason — The sum of kinetic and potential energy does not remain constant throughout the motion of a pendulum. It varies as the pendulum swings due to the interconversion of kinetic and potential energy. However, the sum of kinetic and potential energy is constant if we consider the entire system (kinetic energy + potential energy = mechanical energy), as long as there are no external forces like friction acting on the pendulum.

💡 Some Related Questions

The figure alongside shows a simple pendulum of mass 200 g. It is displaced from the mean position A to the extreme position B. The potential energy at position A is zero. At position B the bob is raised by 5 m.
(a) What is the potential energy of the pendulum at position B ?
(b) What is the total mechanical energy at point C?
(c) What is the speed of the bob at position A when released from position B ? (Take g = 10 ms^-2)

The bob of a simple pendulum is imparted a velocity of 5 m s^-1 when it is at its mean position. To what maximum vertical height will it rise on reaching at its extreme position if 60% of its energy is lost in overcoming the friction of air? (Take g = 10 m s^-2).

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(Take g = 10 ms^-2).

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Name the type of energy possessed by the bob of a simple pendulum when it is at
(a) the extreme position,
(b) the mean position, and
(c) between the mean and extreme positions.