Question

A solid cylinder of radius r and height h is placed over other cylinder of same height and radius. The total surface area of the shape so formed is 4πrh + 4πr².

Options

• True

• False

Answer 1

This statement is False.

Explanation:

Since, the total surface area of cylinder of radius r and height h = 2πrh + 2πr² 

When one cylinder is placed over the other cylinder of same height and radius,

Then height of the new cylinder = 2h

And radius of the new cylinder = r

∴ Total surface area of the new cylinder

= 2πr(2h) + 2πr² 

= 4πrh + 2πr²