Question

Why do seeds of mustard show repulsion when poured in an open plate after being rubbed in a polythene bag...?​

Answer 1

Answer:

Today just now while I was filling rice into a polythene bag. I noticed that some grains inside the polythene bag were sticking to the sides of the bag. I tried to replicate this on the outside of the bag and got positive results.

I am now searching for a reason as to why this is happening. My guess is that static electricity is involved. However that raises the question how does filling rice in a plastic bag result buildup of charges on the rice grains and polythene.