Question

A right cylindrical shaped oil tank of height 40 m is completely filled in 20 minutes. If oil filled at a rate of 8$\pi$ cubic meter per minute, then find the radius of the tank.

• A. 4 m
• B. 2 m
• C. 1 m
• D. 3 m

Answer 1

The correct option is B 2 m

Given, Solid:Cylinder
Height, $h=40\text{m}$
Radius, $r=?$
Rate of filling $=8\pi {\text{m}}^3/\text{min}$
Time taken to fill $=20\text{min}$

Volume of the cylinder = $\pi r^{2}h$
Oil in the container after 20 minutes = $8\pi \times 20$
Oil in the container = volume of the cylinder
$\Rightarrow$ $8\pi \times 20$ = $\pi r^{2}40$
$\Rightarrow r=2\text{m}$