A solid copper sphere of radius 6 cm is melted and redrawn into a wire, whose radius of cross-section is 8 cm. Find the length of the wire.

4.5 cm

We know that,

Volume of sphere = \(\frac{4}{3}\)πR³

Volume of cylinder = πr²h

We have,

Radius of the sphere = R = 6

radius of the cylinder = r = 8

According to the question,

= πr²h = \(\frac{4}{3}\)πR³

= 8 × 8 × h = \(\frac{4}{3}\) × 6 × 6 × 6

= 64  × h = \(\frac{4}{3}\) × 216

= h = 4.5 cm