Question

A light mass and a heavy mass have equal momentum. Which will have more kinetic energy?

April 17, 2024

Answer

Kinetic energy (K) and momentum (p) are related as

K = $p^2\over 2m$

As both masses have the same momentum p. The kinetic energy k is inversely proportional to the mass of the body.

Hence, a body of light mass has more kinetic energy as the smaller the mass, the larger is its kinetic energy.

💡 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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(c) What happens to the mechanical energy after the ball hits the ground and comes to rest?

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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.