Question

If the height of a cylinder is doubled and radius remains the same, then volume will be

(a) doubled (b) halved

(c) same (d) four times

Answer 1

If r be radius and h be the height, then

Volume of a cylinder = $\pi r^2$ h

If height is doubled and radius remain same,

then volume = $\pi r^2\left(2h\right)=2\pi r^2$ h

$\therefore$ It becomes 2 times the original volume.

hence the correct answer is (a) doubled