The diameter of a solid sphere of copper is 6 cm. The sphere is melted to form a wire. If the diameter of the wire is 0·5 cm, then what is the length of the wire?
A.5·24 m
B.5·36 m
C.5·76 m✓ Correct
D.5·96 m
Explanation
Volume of sphere = (4/3)π·r³ = (4/3)π·3³ = 36π cm³. Volume of wire (cylinder) = π·R²·L, where R = 0.25 cm. So π·(0.25)²·L = 36π, giving L = 36/0.0625 = 576 cm = 5.76 m.
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