Question

We have read conductors and insulaters and in that we have read that plastic are bad conductors of electricity, but in the upper activity it is written that plastic comb get charged by electrons ?

Answer 1

Conducting and getting charged are two different phenomena. A body conducts or not depends on the number density of free charge in it, but when we are saying that a body is charged that means it has some discrepancy in charge which means either it has excess number of charge or less number of charge. It can be achieved by the loss or gain of electrons by the body, so charging of insulator is valid despite of this that it is a bad conductor.