Question

How many litres of water will a hemispherical tank hold whose diameter is 4.2m?

Answer 1

Given,
Diameter = 4.2m
Radius = 2.1m
Volume of hemispherical tank =
$2 \div 3 \times\pi \times 2.1 \times 2.1 \times 2.1$
$2 \div 3 \times 22 \div 7 \times 2.1 \times 2.1 \times 2.1$
= 19.404 meter cube

Answer 2

Given :

Diameter of hemispherical tank = 4.2 m

To Find :

How many litres of water will a hemispherical tank hold whose diameter is 4.2m?

Solution:

Diameter of hemispherical tank = 4.2 m

Radius of hemispherical tank =$\frac{4.2}{2} = 2.1 m$

Volume of hemispherical tank =$\frac{2}{3} \pi r^3$

Volume of hemispherical tank= $\frac{2}{3} \times \frac{22}{7} \times 2.1^3$

Volume of hemispherical tank=$19.404 m^3$

1 cubic m = 1000 liters

So, 19.404 cubic m = $1000 \times 19.404=19404 liters$

So, Volume of hemispherical tank in liters = 19404  liters

Hence A hemispherical tank hold 19404 liters of water whose diameter is 4.2m