2014 · Q18
The diameter of a metallic sphere is 6 cm. The sphere is melted and drawn into a wire of uniform circular cross-section. If the length of the wire is 36 m, then what is its radius equal to?
Elementary MathematicsMensuration
- A0.1 cm
- B0.01 cm
- C0.001 cm
- D1.0 cm
Explanation
Sphere volume = (4/3)π·27 = 36π cm³ = πr²·3600, so r² = 0.01 and r = 0.1 cm.