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प्रश्न
12 spheres of the same size are made from melting a solid cylinder of 16 cm diameter and 2 cm height. The diameter of each sphere is
विकल्प
\[\sqrt{3}\] cm
2cm
3cm
4cm
उत्तर
The volume of solid cylinder = 12 × volume of one sphere
`pi xx (8)^2 xx 2 = 12 xx 4/3 pi r^3`
`128=16r^3`
`r^3 = 128/16`
`r = 3sqrt(64/8)`
`=4/2`
`r = 2 cm`
The required diameter d = 2 × 2 = 4 cm
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