Let r and h be the radius and height of the cylinder, respectively.
∴ Curved surface of the original cylinder, C1 = 2rh
If the radius is doubled and height is halved, then
Radius of the new cylinder, R = 2r
Height of the new cylinder, H =
∴ Curved surface of the new cylinder, C2 = = 2rh
Thus, the curved surface area of the new cylinder is same as the curved surface area of the original cylinder.
In a cylinder, if radius is doubled and height is halved, curved surface area will be __same__.