Question

Why does a glass rod become positively charged when it is rubbed with a silk cloth?

Answer 1

The protons from the glass rod are transferred to the silk cloth.

The glass is the material creating the charge not the cloth. And the charge from the glass is positive while the charge from the silk is negative.

Answer 2

Answer: The electrons from the glass rod are transferred to the silk cloth.

When glass rod is rubbed with a silk cloth, there is transfer of electrons from the glass rod to the silk cloth. Hence, the glass rod becomes positively charged because of loss of electrons and silk cloth becomes negatively charged because of gain of electrons. This method of charging is known as charging by friction.