Question

$2.2d{m}^3$ of brass is to be drawn into a cylindrical wire of diameter $0.50cm$. Find the length of the wire.

Answer 1

Concept: 1 Mark

Volume of brass
$=2.2d{m}^3=(2.2\times 10\times 10\times 10)c{m}^3=2200c{m}^3(1dm=10cm)$

Let the required length of wire be $x$ cm.

Then, its volume
$=\left(\pi r^{2}x\right)c{m}^3=2200c{m}^3$

$\Rightarrow \frac{22}{7}\times 0.25\times 0.25\times x=2200$

$\Rightarrow x=11200cm=112m.$ $(\because 100cm=1m)$

Hence, the length of wire is $112m$.