Question

A body is moved in straight line by constant power of machine. What will be the relation between the travelling distance and time?

• A. $s^2\propto t^3$
• B. $s^2\propto t^5$
• C. $s^3\propto t^2$
• D. $s\propto t^3$

Answer 1

The correct option is A $s^2\propto t^3$

Power of a moving object $P=F.v$

$=ma.v$

We know that $s=\frac{1}{2}a{t}^2$

$⟹a=\frac{2s}{t^2}$

Also $v=at=\frac{2s}{t}$

Thus , $P=m.\frac{2s}{t^2}.\frac{2s}{t}$

$⟹s^2\propto t^3$