Mensurationmedium · Past Paper
A solid lead ball of radius 7 cm was melted and then drawn into a wire of diameter 0.2 cm. Find the length of the wire.
A457.33 m
B45.73 m
C4573.3 m
D4.57 m
✓ Correct Answer: A — 457.33 m
Vol_sphere = (4/3)π(7³). Vol_wire(cylinder) = π(0.1²)L. (4/3)343 = 0.01L => L = 45733.3 cm = 457.33 m.
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