A body is initially at rest. It undergoes one-dimensional motion with

solution:

Answer: (ii) t

Mass of the body = m

Acceleration of the body = a

Using Newton’s second law of motion, the force experienced by the body is given by the equation:

F = ma

Both m and a are constants. Hence, force F will also be a constant.

F = ma = Constant … (i)

For velocity v, acceleration is given as,

$a=\frac{d v}{d t}=$ Constant

$d v=$ Constant $\times d t$

$v=\alpha t$ $\ldots(i i)$

Where, $\alpha$ is another constant

$v \propto t$ $\ldots$ (iii)

Power is given by the relation:

P = F.v

Using equations (i) and (iii), we have:

$P \propto t$

Hence, power is directly proportional to time.