Question

(a) A body of mass m is moving with a velocity v. Write the expression for its kinetic energy. (b) Show that the quantity 2K/v² has the unit of mass, where K is the kinetic energy of the body.

April 17, 2024

Answer

(a) The expression for a body of mass m moving with a velocity v is given by

Kinetic Energy (K) = $1\over 2$ × m ×v²

⇒ $2K\over v^2$ = m (mass)

So, Kg is the unit of mass

💡 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)

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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
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