Mensurationhard · Past Paper
The diameter of a copper sphere is 18 cm. It is drawn into a wire of diameter 4 mm. Find the length of the wire.
A243 m
B24.3 m
C2430 m
D121.5 m
✓ Correct Answer: A — 243 m
Vol sphere = 4/3π(9³). Vol wire = π(0.2)²L. 4/3 * 729 = 0.04L. 972 / 0.04 = L. L = 24300 cm = 243 m.
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