Question

It is required to make a closed cylindrical tank of height 1 m and base diameter 140 cm from a metal sheet. How many square meters of the sheet are required for the same?

Answer 1

Height of the cylindrical tank (h)=1m.
Base radius of cylindrical tank (r) = `140/2`m =70 cm 

=0.7m
Area of sheet required – total surface area of tank = 2π (r+h)
=2×3.14×0.7 (0.7 +1) `m^2`

= 4.4×1.7`m^2`
=`7.48m^2`
∴So, it will required  `7.48m^2` of metal sheet.