Q8 of 52 Page 160

The radius of a metallic sphere is 9 cm. It was melted to make a wire of diameter 4 mm. Find the length of the wire.

Radius of sphere, R = 9 cm



Let the length of wire be H


Radius Of wire, r = 2 mm = 0.2 cm


Volume of wire , v = πr2H


As sphere is melted to make a wire,


⇒ V = v





⇒ H = 24300 cm


⇒ H = 243 m


∴ The length of the wire formed is 243 m


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