Q29 of 107 Page 16

The diameter of a metallic sphere is equal to 9 cm. It is melted and drawn into a long wire of diameter 2 mm having uniform cross-section. Find the length of the wire.

Volume of the metallic sphere=volume of the wire(cylinder in shape)


Radius of sphere cm


=4.5 cm


Volume of sphere = 3


3


Radius of cylinder = 1mm =0.1cm


Volume of cylinder r2h


⇒ πr2h 3


⇒ r2h R3


⇒ 0.1 × 0.1 × h = × 4.5 × 4.5 × 4.5


⇒ 0.1 × 0.1 × h =4 × 1.5 × 4.5 × 4.5


⇒ h = 12150 cm


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