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प्रश्न
The volume of a sphere is 38808 cm3; find its diameter and the surface area.
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उत्तर
Volume of the sphere = 38808 cm3
Let radius of sphere = r
∴ `4/3pir^3 = 38808 `
`=> 4/3 xx 22/7 xx r^3 = 38808`
`=> r^3 = (38808 xx 7 xx 3)/(4 xx 22) = 9261`
`=>` r = 21 cm
∴ Diameter = 2r
= 21 × 2 cm
= 42 cm
Surface area = 4πr2
= `4 xx 22/7 xx 21 xx 21`
= 5544 cm2
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