Question

write about the following method of separation

i) hand picking
ii) threshing
iii) winnowing
iv) sieving

Answer 1

Handpicking :This method is used for separating small particles of dirt, stone, husk etc. from the grains of wheat, rice, pulses, etc.
Sieving
(i)            Sieving is used when two component of a mixture have different particle size.
(ii)          Sieving allows the fine particles to pass through the holes of the sieve, while the bigger particles remain on the sieve. For examples, sieving of wheat flour, sieving of sand at construction sites.
Winnowing : Winnowing can be used to separate lighter and heavier components of a mixture. For example : to separate husk from grain with the help of air.
Threshing : The process that is used to separate grain from stalks is threshing.

Answer 2

i) Handpicking :
Bigger and visible component of a mixture can be separated by hand picking it by using forceps.

ii) Threshing:
It is separtion of husk from a crop plant by thresher.

iii) Winnowing :
This allow the separation of light and heavy compincs of a mixture by the help of wind.

iv) Sieving :
Bigger component of a mixture can be easily departed by the uses of sieve.