Question

What is the total surface area of a hemisphere?

• A. 2$\pi$$r^2$
• B. 4$\pi$$r^2$
• C. $\frac{4}{3}$$\pi$$r^2$
• D. 3$\pi$$r^2$

Answer 1

The correct option is D

3$\pi$$r^2$

The lateral surface area of hemisphere is half of the surface area of a sphere which is $\frac{4\pi r^2}{2}=2\pi r^2$.

and the area of the base of the hemisphere is the area of the circle which is $\pi r^2$.

$\therefore$ Total surface area of a hemisphere
= Lateral surface area + area of circular base
= $2\pi r^2$ + $\pi r^2$
= $3\pi r^2$