Question

1 (cm) 3 of gold is drawn into a wire 0.1 mm in diameter find the length of the wire

Answer 1

Volume of the gold = 1 cm^3

In the cylindrical wire ;
r = (0.1/2) = 0.05mm = 0.005 cm
length = h = ?

Volume of cylindrical wire = volume of gold
πr^2h = 1

(22/7) × (0.005×0.005) × h = 1
h = 7/0.00055
h = 14000
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Hence the length of the wire is 14000 cm or 140 m