Q. 19

# 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.

Answer :

Volume of a sphere = (4/3)πr^{3}

Volume of a cylinder = πr^{2}h

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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