Q28 of 107 Page 16

Prove that the surface area of a sphere is equal to the curved surface area of the circumscribed cylinder.

Curved surface area of sphere

Let ‘r’ be the radius of sphere


Height of cylinder=’2r’


Curved surface area of cylinder


⇒


⇒


∴ Surface area of a sphere is equal to the curved surface area of the circumscribed cylinder.


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