Q15 of 56 Page 13

Volume and surface area of a solid hemisphere are numerically equal. What is the diameter of hemisphere?(CBSE 2017)

Let r be the radius of the hemisphere.

Given: Volume of hemisphere = S.A of hemisphere


⇒ (2/3)πr3=3πr2
⇒ (2/3)r=3
⇒ r=9/2
∴ Radius = 9/2 units


Diameter = (9/2) × 2 = 9 units.

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