Question

A petrol tank is a cylinder of base diameter 21 cm and length 18 cm fitted with conical ends each of axis length 9 cm. Determine the capacity of the tank.

Answer 1

To find the total capacity of the tank, we have to add the volume of the cylinder and cone.

Diameter of the cylinder, d = 21 cm

Radius of the cylinder, `r=d/2=21/2cm`

 Height of the cylinder, h₁ = 18cm

Also, radius of cone, `r =21/2cm` 

Height of the cone, h₂ = 9 cm

now,

Total capacity of the tank= Volume of the cylinder + Volume of 2 cones

`pir^2h_1+2xx1/3pir^2h^2`

`=pir^2(h_1+2/3h_2)`

`=22/7xx(21/2)^2xx(18+2/3xx9)`

`22/7xx(21/2)^2xx24`

= 8316 cm³

Hence the total capacity of the tank is 8316 cm³.