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In a cylinder, if radius is doubled and height is halved then what happens to the curved surface area?


A) Halved

B) Doubled

C) Does not change

D) Four times

Correct Answer:
C) Does not change

Description for Correct answer:

The curved surface area of a cylinder = \( 2\pi rh \)

If radius (r) is doubled and height (h) is halved

The curved surface area of a cylinder

=\(2\pi \times 2r \times \frac{h}{2}\)

Hence the curved surface area of the cylinder does not change. 


Part of solved TNPSC Question Paper-2015 questions and answers : Exams >> TNPSC >> TNPSC Question Paper-2015




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