Question

1 $c{m}^3$ of gold is drawn into a wire 0.1 mm in diameter.Find the length of the wire.

Answer 1

Volume of the gold = $1c{m}^3$
$1c{m}^3$ = 1000 mm
Diameter of wire = 0.1 mm
radious of a wire = 0.1/2 = 0.05 mm
Now ,
volume of the gold in wire = volume of gold
$\pi r^{2}h=1000mm$
$\frac{22}{7}\times 0.5\times 0.5\times h=1000mm$
0.055h. = 7000 mm
h = $\frac{7000}{0.055}$
h = 127272 mm
or ,
h = $\frac{127272}{1000}m$
= 127 m ( Approx )