Question

If the height and radius of a cone are doubled, then the volume of the cone becomes

• A. 2 times
• B. 4 times
• C. 8 times
• D. 10 times

Answer 1

Answer: (C)

8 times

Let, height of cone$=h$

Radius $=r$

Volume$=v$

Now, $v=\frac{\pi r^{2}h}{3}$

As per condition if height and radius of the cone are doubled,

Then volume,

$v=\pi {\left(2r\right)}^2\frac{2h}{3}$

$v=8.\left(\pi r^2\frac{h}{3}\right)$

Hence, if the height and the radius of the cone are doubled, then the volume becomes eight times.

Hence, Option C is correct.