Consider the following statements. A and B and identify the correct answer given below. Body initially at rest is acted upon by a constant force. The rate of change of its kinetic energy varies linearly with time. When a body is at rest, it must be in equilibrium.

Question

Dr. Abubacker · Accepted Answer

(c) KE$= \frac{1}{2}mv^{2} = \frac{1}{2}m(at)^{2} = \frac{1}{2}ma^{2}t^{2}$
Rate of change of KE,
$\frac{dk}{dt} = \frac{d}{dt}\left( \frac{1}{2}ma^{2}t^{2} \right) = ma^{2}t$
$\because\ \frac{dk}{dt} \propto t$
So, statement $A$is correct.
When the body is at rest then it may be or may not be in equilibrium, so statement $B$is wrong.

Q. Consider the following statements. A and B and identify the correct answer given below. Body initially at rest is acted upon by a constant force. The rate of change of its kinetic energy varies linearly with time. When a body is at rest, it must be in equilibrium.

Explanation

Reviewed by Dr. Abubacker

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