Q20 of 49 Page 1

A solid metallic sphere of diameter 8 cm is melted and drawn into a cylindrical wire of uniform width. If the length of the wire is 12 m, find its width.

Volume of the sphere = πr3 =

= cm3


Volume of a cylindrical wire = πr2h


Given, length (height) of the wire = 12 m


⇒ πr2h =


⇒ r2 = = 4096


⸫ r = √4096 = 64 cm


⸫ Width of the wire = 2 × 64 = 128 cm


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