Question

If the diameter of the base of a closed right circular cylinder be equal to its height h, then its total surface area is

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

Answer 1

The correct option is C $\frac{3}{2}\pi h^2$

Given that the diameter of the base of a cylinder = The height of the cylinder
$⟹Radius,r=\frac{h}{2}$

Total surface area of the cylinder
$=2\pi r(h+r)$

$=2\pi \frac{h}{2}(h+\frac{h}{2})$

$=2\pi \frac{h}{2}\times \frac{3h}{2}$

$=\frac{3}{2}\pi h^2$