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प्रश्न
A solid sphere of radius r is melted and cast into the shape of a solid cone of height r, the radius of the base of the cone is
विकल्प
2r
3r
r
4r
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उत्तर
Volume of sphere = volume of the cone
`4/3 pir^(3^3) = 1/3 piR^2 xx r`
`R^2 = 4r^2`
`R = 2r`
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