A solid copper sphere of radius 6 cm is melted and recast into a wire of radius 0.1 cm. Find the length of the wire.

Explanation

Volume of sphere = (4/3)*pi*r^3 = (4/3)*pi*216 = 288*pi cm³. Volume of cylinder wire = pi*r^2*h = pi*(0.1)^2*h = 0.01*pi*h. Equating: 0.01*h = 288 => h = 28,800 cm = 288 m.