Question

A closed cylindrical tank of diameter $21m$ and height $4m$ is made of steel. How much area of steel sheet is required?

Answer 1

Given,

diameter of cylindrical tank $=21m$.

height of cylindrical tank $=4m$.

Then, radius $r=\frac{21}{2}=10.5$

Total Surface Area of Cylinder

$=2\pi r(h+r)$

$=2\times 3.14\times 10.5(4+10.5)$

$=2\times 3.14\times 10.5\times 14.5$

$=956.13m^2$

Total steel sheet required to make tank is $=956.13m^2$