ICSE Class 8 Answered

When you rub a plastic comb against your dry hair, it makes some particles move between the comb and your hair.

 Some of these particles move from your hair to the comb and some move from the comb to your hair. These particles are called electrons. The object which gets these extra electrons, we say that the object is negatively charged. And when something loses electrons, it becomes positively charged.

So, after you comb your hair with the plastic comb, the comb acquires electrons, making it negatively charged and your hair loses some electrons, so it becomes positively charged.

We can verify this by bringing the charged comb close to tiny bits of paper or tiny pieces of hair, they either stick to the comb or move away from it. This is because opposite charges attract each other, so the positively charged hair is attracted to the negatively charged comb.