Question

$15$ circular plates, each of radius $7cm$ and thickness $3cm$ are placed one above the another to form a cylindrical solid. Find the volume of the cylinder so formed.

Answer 1

Number of circular plates $=15$

Radius of each plate $=7cm$

Thickness of each plate $=3cm$

As the plates are stacked one above the other, so the height of the cylindrical solid formed $=15\times$ thickness of each plate

$=15\times 3=45cm$

Now volume formed :

$=\pi r^{3}h=\frac{22}{7}\times {\left(7\right)}^3\times 45=6930{cm}^3$