Question
Download Solution PDFFind the surface area (in cm2) of a sphere whose diameter is 21 cm.
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFGiven:
Diameter of sphere = 21 cm
Formula used:
Surface Area of Sphere = 4πr2
Where, r = radius of the sphere
Calculation:
Radius (r) = Diameter ÷ 2
⇒ r = 21 ÷ 2 = 10.5 cm
Surface Area = 4 × π × r2
⇒ Surface Area = 4 × 22/7 × (10.5)2
⇒ Surface Area = 1386 cm2
∴ The correct answer is option (3).
Last updated on Jul 8, 2025
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