Question

If the triangle $ABC$ in the question $7$ above is revolved $7$ above is resolved the side $5cm$, then find the volume of the solid so obtained Find also ratio of the volumes of the two solids obtained in Questions $7$ and $8$.

Answer 1

Here $r=12$,

$h=5$

$\Rightarrow v=\frac{1}{3}\pi r^{2}h=\frac{\pi }{3}\left(144\right)\times 5=\frac{720}{3}\pi$

Ratio $=\frac{100\pi }{720\pi }\times 3=\frac{30}{72}=\frac{5}{12}$.