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प्रश्न
The volume of a sphere is 4851 cm3. Find its curved surface area.
उत्तर
Let the radius of the sphere be r.
As,
Volume of the sphere = 4851 cm3
`=> 4/3pi"r"^3 = 4851`
`=> 4/3xx22/7xx"r"^3 = 4851`
`=> "r"^3=4851xx(3xx7)/(4xx22)`
`=>"r"^3 = 9261/8`
`=r=root(3)(9261/8)`
`=>r =21/2 "cm"`
Now,
Curved surface area of the sphere = 4πr2
`=4xx22/7xx21/2xx21/2`
= 1386 cm2
So, the curved surface area of the sphere is 1386 cm2.
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