difference between hand picking and threshing
Answers
Answer:
Handpicking: It is the simplest method of separation of substances. This method is used only when unwanted material is in small quantity. Moreover, shape, size, or colour of the unwanted material is different from that of the useful materials. For example; pebbles, broken grains and insects are separated from rice, wheat and pulses; by handpicking.
Threshing: Threshing is used for separating seeds from the harvested stalks.
Manual Threshing: When the quantity is small, threshing is done manually. Small bundles of the harvested stalks are thrashed on a hard surface. This helps in separating the grains.
Threshing by Animals: For larger quantities, threshing is done in the traditional way; by using animals. For this, stalks are spread around a pole. Several bullocks are tied to the pole and are made to walk over the harvested stalks. Trampling by hooves of the animals helps in separating grains.
Threshing Machine: Now-a-days, threshing machines are used for the purpose. It can be powered by either a diesel engine or an electric motor. It helps in saving time and labour.
Answer:
The method in which substances in a mixture can be separated by just picking them out with the help of hand from the mixture is known as handpicking method. It is one of the various methods which are carried out in dry conditions.
threshing =separate grain from (corn or other crops), typically with a flail or by the action of a revolving mechanism.