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 round on the longer side.Find the volume of the solid,thus generated.Also,find its curved surface area.

Answer 1

Length of sides of a right angled triangle are 6.3 cm and 10 cm

By turning around the longer side,a cone is formed in which radius (r)=6.3 cm and height (h)=10 cm

$\therefore l=\sqrt{r^2+h^2}=\sqrt{(6.3{)}^2+(10{)}^2}=\sqrt{39.69+100}=\sqrt{139.69}cm=11.82cmNowvolume=\frac{1}{3}\pi r^{2}h=\frac{1}{3}\times \frac{22}{7}\times (6.3{)}^2\times 10c{m}^2=\frac{22}{21}\times 6.3\times 6.3\times 10=415.8c{m}^{3}andcurvedsurfacearea=\pi rl=\frac{22}{7}\times (6.3)\times 11.82c{m}^2=234.03c{m}^2$