Question

The capacity of a closed cylindrical vessel of height $1$ m is $15.4$ litres. How many square metres of metal sheet would be needed to make it?

Answer 1

Given:

$\Rightarrow$$h=1$m, $V=15.4l=0.0154$ m${}^3$

$\Rightarrow$Let radius $=r$

$\Rightarrow$$V=\pi .r^2.h$

$\Rightarrow$$0.0154=\pi r^{2}h=\frac{22}{7}\times r^2\times 1$

$\Rightarrow$$r=0.07$m

$\Rightarrow$Total Surface Area$=2\pi r^2+2\pi rh$

$\Rightarrow$$2\times \frac{22}{7}\times 0.07(0.07+1)$

$\Rightarrow$$0.44\times 1.07$m${}^2$

$\Rightarrow$$0.4708$m${}^2$