Q19 of 70 Page 21

The diameter of a sphere is 6 cm. It is melted and drawn into a wire of diameter 0.2 cm. Find the length of the wire.

Volume of a sphere = (4/3)πr3


Volume of a cylinder = πr2h


Given, diameter of a sphere is 6 cm. It is melted and drawn into a wire of diameter 0.2 cm.


Long wire can be assumed to be a cylinder.



⇒ l = 3600 cm = 36 m


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