Question

A rectangle of length “$a$” and breadth “$b$” is rotated by ${360}^{\circ }$ about its length. The volume of the resulting cylinder is _____.

• A. $\pi a{b}^2$
• B. $\pi a^{2}b$
• C. $\pi ab$
• D. $2\pi ab$

Answer 1

The correct option is A $\pi a{b}^2$

Height of the cylinder
$=lengthoftherectangle$
${=}^{\prime }{a}^{\prime }units$

Radius of the cylinder
$=Breadthoftherectangle$
${=}^{\prime }{b}^{\prime }units$



Volume of the cylinder
$=\pi r^{2}h$
Where, $r$ is the radius of the cylinder and $h$ is the height of the cylinder.

So, volume of the formed cylinder
$=\pi b^{2}a$
$=\pi a{b}^2$