What is the change in the curved surface area of a cylinder when we double the radius and the height is halved?
Show answer & explanation
Correct answer: D
Explanation
The correct answer is Option 4 i.e. No change
Let the original radius be r and the original height be h
Then the new radius be 2r and the height will be h/2
Curved surface area of a cylinder is = 2π(R)h
Original curved surface area = 2πrh
= 2π×2r×h/2
=2πrh
Hence the area will be same