Write the unit and value of the fundamental electric charge.

Give reason: 'Small and light pieces of paper are attracted by a comb run through dry hair.'

The statement that electric charge is an integral multiple of the electronic charge $e$ was experimentally proven by whom?

How can you represent experimentally that $(i)$ there are two types of charges and $(ii)$ there is repulsion between two like charges and attraction between two unlike charges?

Which of the following properties is $NOT$ satisfied by a static electric charge?

Two identical spherical conductors $B$ and $C$ have equal radii and carry equal charges. They repel each other with a force $F$ when placed at a certain distance apart. $A$ third identical spherical conductor $A$,which is uncharged,is brought in contact with $B$ and then removed. It is then brought in contact with $C$ and removed. What is the new force of repulsion between $B$ and $C$?