Question

Question 107

Metallic discs of radius 0.75 cm and thickness 0.2 cm are melted to obtain 508.68 $c{m}^3$ of metal. Find the number of disc melted. (Use $\pi =3.14$)

Answer 1

Radius of metallic disc = 0.75 cm
Thickness of disc = 0.2 cm
Total volume of material which will be used in forming/melting of disc $=508.68c{m}^3$
$\therefore$ Material required for one disc = Volume of cylinder.
$=\pi r^{2}h=\frac{22}{7}\times 0.75\times 0.75\times 0.2$ [$\because$ shape of a disc is a cylinder]
$=3.14\times 0.75\times 0.75\times 0.2$
$=0.35325c{m}^3$.
Number of discs can be melted $=\frac{Totalvolumeofmetalobtainedaftermelting}{Volumeofonedisc}$
$=\frac{508.68}{0.35325}=1440$ discs