Question

A right angled triangle of which the sides containing the right angle are $6.3$cm and $10$cm in length, is made to turn around on the longer side. Find the volume of the solid thus generated.

Answer 1

We know that the volume of a right circular cone with radius $r$ and height $h$ is $V=\frac{1}{3}\pi r^{2}h$.

It is given that the height of the solid is $h=10$ cm and radius is $6.3$ cm, therefore,

$V=\frac{1}{3}\pi r^{2}h=\frac{1}{3}\times \frac{22}{7}\times (6.3{)}^2\times 10=\frac{1}{3}\times \frac{22}{7}\times 39.69\times 10=415.8$cm${}^3$

Hence, the volume of the solid is $415.8$ cm${}^3$.