Types of Charging

Key Concepts

• Charging by friction
• Charging by contact
• Charging by induction

Introduction

Charging by friction  

Consider a plastic rod with no charge. If the rod is rubbed with a cloth, consider silk cloth, then the plastic rod accumulates positive charge. Can you guess why the plastic rod gets charged positively after being rubbed with the silk cloth. 

Charging by friction: 

When the plastic rod is rubbed with the silk cloth it accumulates positive charge due to the friction. And if the plastic rod is brought to the paper pieces, it attracts the paper pieces, proving there is a charge present in the plastic rod. 

Do it yourself: 

Take a plastic rod and take it near to paper pieces. Observe if the paper pieces are attracted to the plastic rod or not. 

Now, rub the plastic rod with a silk cloth for some time. Positive charges are accumulated in the plastic rod. Bring the plastic rod near to the Note your observations. 

Do this with different plastic materials and note your observations. 

Points to be remembered in force by friction: 

1. The plastic rod is neutral at the beginning.  

2. After the rod is rubbed with the silk cloth, then due to friction, charge is accumulated. 
3. The rod will be positively charged. 

Do it yourself: 

Take a rubber balloon, blow air into the balloon and bring the balloon to the thermal balls. Then you can observe that the thermocol balls are not attracted to the balloon. 

Now, rub the balloon to your body for some time and bring the balloon to the thermocol balls. Now you can observe that the balls are attracted to the balloon. 

Charging by conduction: 

Consider a charged sphere which is connected to an electric source and it is charged with both the negative and the positive charge. Now, take a metal rod and keep it near the charged sphere, then the rod which is brought near to the sphere is also charged, either negatively or the positively. This mode of charging is called charging by conduction.   

Charging by induction: 

The process of charging a non-charged body with a charged body without physical contact is called induction. 

In the induction, one body is charged as another body is kept in the phase of the electric field radius; hence the charged body will give charge to the uncharged body with opposite polarity without even touching it. This is called charging by induction. 

Summary

Types of Charging:

1. Charging by friction
2. Charging by conduction
3. Charging by induction

Charging by friction:

The transfer of electrons from one uncharged object to. another by rubbing the two objects together.

Charging by conduction:

The process of charging the uncharged object by bringing it in contact with another charged object is called charging by conduction.

Charging by the induction:

The process of charging a non-charged body with a charged body without actually having a

physical contact is called induction.