The radius of a sphere is 9 cm. It is melted and drawn into a wire of radius 0.3 cm. The length of the wire is:
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Correct answer: B
Explanation
The correct answer is option 2 i.e. 108 m
The volume of sphere of radius 9 cm is (4/3)π × (0.09)3 = 0.000972π m3
Diameter of the wire 0.3cm = 0.03 m
⇒ The radius of the wire is 0.015 m
Let, the length of the wire is h
The volume of the wire is π(0.015)2 × h = πh/1000000 m3
Accordingly, h = 108