Question

Mark the correct alternative in each of the following:

In a cylinder, if radius is doubled and height is halved, curved surface area will be

(a) halved

(b) doubled

(c) same

(d) four times

Answer 1

Let S₁ be the curved surface area of the cylinder with radius r₁ and height h₁, then

……. (1)

Now, let S₂ be the surface area after changing the dimension, then

So,

Hence, the correct option is (c)