Question

The solid object is composed of a hemisphere and a cone surmounted on it. If the common radius is 7m and height of the cone is 1m, what is the volume?

• A. 262.39 $m^2$
• B. $770m^3$
• C. 662.39 $m^2$
• D. 563 $m^2$

Answer 1

The correct option is B

$770m^3$

Volume of the surface = Volume of the hemisphere + Volume of the cone
$V=\frac{2}{3}\pi r^3+\frac{1}{3}\pi r^{2}h$

$\pi =\frac{22}{7};r=7m;h=1m$
$V=(\frac{2}{3}\times \frac{22}{7}\times 7\times 7\times 7+\frac{1}{3}\times \frac{22}{7}\times 7\times 7\times 1)m^3=770m^3$
$770m^3$