Question

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

• A. $3$ times
• B. $4$ times
• C. $6$ times
• D. $8$ times

Answer 1

The correct option is D $8$ times

Volume of the original cone
$=\frac{1}{3}\pi r^2=V_1$
Volume of the new cone
$=\frac{1}{3}\pi {\left(2r\right)}^2.2h=v_2$
$\therefore V_2=8\times \frac{1}{3}\pi r^{2}h$
$=8\times$ volume of original
i.e. $V_2=8V_1$