Question

The curved surface areas of a right circular cylinder and a sphere are equal.

Also, the radii of the cylinder and sphere are equal.

Then the ratio of their volume will be?

• A. $2:3$
• B. $3:2$
• C. $3:4$
• D. $4:3$

Answer 1

Answer: (B)

$3:2$

Curved surface of right circular cylinder $=$ Curved surface of sphere
$\therefore 2\pi RH=4\pi R^2$
$\therefore H=2R$
$\frac{VolumeofCylinder}{VolumeofSphere}=\frac{\pi R^{2}H}{\frac{4}{3}\pi R^3}$
$=\frac{H}{\frac{4}{3}R}$

$=\frac{2\times 3}{4}$
$=3:2$