Question

A cylinder has a diameter of $20cm$. The area of the curved surface is $100c{m}^2$ (sq. cm). Find the height of the cylinder correct to one decimal place.

Answer 1

Given,

The diameter of the cylinder$=20cm$

So, the radius (r)$=10cm$

And the curved surface area$=100c{m}^2$

Height = h cm

Curved surface area$=2\pi rh$

So,

$2\pi rh=100c{m}^2$

$2\times \frac{22}{7}\times 10\times h=100$

$h=\frac{(100\times 7)}{(22\times 10\times 2)}=\frac{35}{22}$

$h=1.6cm$ approx