Page:Calculus Made Easy.pdf/86

Find an expression for the velocity and the acceleration at any time. Find the velocity and acceleration after $10$ seconds.

(10) A body moves in such a way that the spaces described in the time $t$ from starting is given by $s=t^{n}$, where $n$ is a constant. Find the value of $n$ when the velocity is doubled from the $5$th to the $10$th second; find it also when the velocity is numerically equal to the acceleration at the end of the $10$th second.