Question

How could we predict what charge will be on which object when rubbed? For example when fur with cat skin etc.

Answer 1

When two objects are rubbed they acquire charge due to friction. Both the objects acquire two different types of the charge but we can not predict which charge will have positive charge or which will have negative charge.


Charging Objects by Friction Charging by Friction: is the transfer of electrons between two neutral objects, (made from different materials), that occurs when they are rubbed together or come in contact (touch).

- If two neutral objects are rubbed together, then each will become charge (friction).
- Electric charges are transferred from one object to the other.
- One object becomes negatively charged as it accumulates electrons, the other one becomes positively charged as it loses electrons.
- Combing hair is an excellent example of charging by contact, or by friction.
- Objects are easily charged during the winter because the air is dry.
- During the summer the humidity is high (water vapour in the air), it is more difficult to charge objects.
- Water vapour makes contact with charged objects and electrons are passed form the object to the water vapour molecules.
- Some objects can be charge just by touching (contact).