Q19 of 51 Page 1

The diameter of a metallic sphere is 6 cm. The sphere is melted and drawn into a wire of uniform cross-section. If the length of the wire is 36 m, find its radius.


Given: diameter of metallic sphere = 6 cm


Length of the wire = 36 m


To find: The radius of the wire.


Formula Used:


Volume of the cylinder = πr2h


Volume of sphere =


Explanation:


Radius of sphere = = 3 cm


Volume of sphere =



= 36π cm3


Let the radius of cross-section of wire be “r” cm.


Length of wire = 36 m = 3600 cm


Volume of wire = (π× r2× 3600) cm2


As metallic sphere is converted into the cylindrical shaped wire.


⇒ The volume of the wire = volume of the sphere


⇒ π× r2× 3600 = 36π




⇒ r = 0.1 cm


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