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A cylindrical rod of iron, whose height is equal to its radius ,is melted and cast into spherical balls whose radius is half the radius of the rod. find the number of balls.

A cylindrical rod of iron, whose height is equal to its radius ,is melted and cast into spherical balls whose radius is half the radius of the rod. find the number of balls. Correct Answer 6

Volume of cylinder = πr2h [Here h = r] = πr2×r = πr3 Volume of sphere = 4/3 πr3  [Here r = r/2) = (4/3) π× (r/2)3 = (πr3)/6 Number of balls = πr3/( πr3/6) = 6  ans: 6

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