Question

30 circular plates, each of radius 14 𝑐𝑚 and thickness 3 𝑐𝑚, are placed one above the other to form a cylindrical solid. Find the TSA and the volume of the cylinder so formed.

Answer 1

When the circular plates are stacked one above the other they will form a cylinder.
Given: r = 14 cm, Thickness of a circular plate = 3 cm, Number of plates = 30
Therefore, the height of the cylinder will be $3\times 30=90cm$.

Total surface area of a cylinder
$=2\pi r(h+r)$
$=2\times \left(\frac{22}{7}\right)\times 14\times (90+14)$
$=9152c{m}^2$
Volume of the cylinder $=\pi r^{2}h$
$=\left(\frac{22}{7}\right)\times {14}^2\times 90$
$=55440c{m}^3$