Question

The rainfall recorded on a certain day was 5cm. Find the volume of water that fell on a 2 hectare field?

Answer 1

Hint: We will first convert hectare into ${{m}^{2}}$. As we know that $1hectare=10000{{m}^{2}}$ then we convert the height rain to metre, and finally we will find the volume of water by multiplying the area of the field with the height of rain.

Complete step-by-step answer:
It is given in the question that the rain recorded on a certain day was 5cm. Also, the area of the field in which observation was taken is a 2 hectare field, then we have to find the volume of the water that fell on that day. First of all, we will convert both area of field and rainfall into metre because both of them are given in different data.
Conversion of 5cm rainfall into metre. We know that $1m=100cm$, So we get $5cm=0.05metre$, thus volume of rainfall is 0.05m. Now we will convert the field area which is given in hectare into metre. We know that $1hectare=10000{{m}^{2}}$, therefore, we get $2hectare=2\times 10000{{m}^{2}}=20000{{m}^{2}}$.
Now the volume of the water that fell on that day will be calculated as Area of field multiplied with height of rainfall. We have an area of field = 20000${{m}^{2}}$, also height of rainfall = 0.05m. Thus, the volume of water in the field will be $=20000{{m}^{2}}\times 0.05m$ $=1000{{m}^{3}}$. We can convert ${{m}^{3}}$ into litres as $1{{m}^{3}}=1000l$, therefore,
$1000{{m}^{3}}=(1000\times 1000)L$
$={{10}^{6}}litres$
Therefore the volume of the water in the field will be ${{10}^{6}}litres$ on that day.

Note: Students may do wrong calculations by skipping the conversion of the field area and rainfall into the same units. If we do not do the conversion then the answer which we get will be wrong because both of them are given in different units. Best way is to always work in the SI units for every such conversion based question.