Question

Explain why the surface of mortar and pestle (silbatta) used for grinding is etched again after prolonged use?

Answer 1

Step 1. Mortar and pestle:

1. Mortar and pestle, are ancient devices for milling by pounding.
2. The mortar is a medium-sized bowl generally made of stone, ceramic, or wood.
3. The pestle is a round grinding rod type often made of the same material as the mortar.

Step 2: Explanation:

1. When we use them for a long time, they lose their roughness.
2. Hence the frictional force between them decreases and they stop working correctly.
3. As we know, we can increase the frictional force by etching.
4. Thus we have to etch it to make it rough again.

Hence the surface of the mortar and pestle is etched again to increase the frictional force between them.