The numerical value of the volume of a sphere is twice the numerical value of its surface area. Find the radius of the sphere.
WBBSE
Class X
Mathematics
Sphere
02 Mark
2023
Volume of the sphere = 4\over3πr³
Surface area of the sphere = 4πr²
Given that the volume is twice the surface area:
⇒ 4\over3πr³ = 2 × 4πr²
⇒ 4\over3r³ = 8r²
⇒ 4\over3r = 8
⇒ 4r = 24
⇒ r = 6
Thus, the radius of the sphere is 6 units.
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