Question

What's the radius of the hemisphere if the total surface area of the hemisphere is $27\pi c{m}^2$?

• A. 3 cm
• B. 27 cm
• C. 9 cm
• D. 12 cm

Answer 1

The correct option is A 3 cm

We know that,
total surface area of hemisphere
$=3\pi r^2$

Given that,
$3\pi r^2=27\pi$
$\Rightarrow r^2=9$
$\Rightarrow r=3cm$

$\therefore$ The radius of the hemisphere is 3 cm.