Question

What is winnowing? Where is it used?

Answer 1

$\bullet$ Winnowing is the process of separating substances based on the difference in weights of the constituent components. It is used when the impurities are much lighter than the desired substance such that the impurities can be carried away by the wind.
$\bullet$ For example, husks are separated from grains using winnowing as husks are lighter and get carried away by the wind, whereas grains are heavier.