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प्रश्न
A spherical ball of radius r1 units is melted to make 8 new identical balls each of radius r2 units. Then r1 : r2 is
पर्याय
2 : 1
1 : 2
4 : 1
1 : 4
उत्तर
2 : 1
Explanation;
Hint:
Volume of the first sphere : Volume of second sphere = 8 : 1
`4/3pi"r"_1^3 : 4/3 pi"r"_2^3` = 8 : 1
`"r"_1^3 : "r"_2^3` = 23 : 13
r1 : r2 = 2 : 1
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