Tag: charging by induction

Insulators are the materials that do not allow electrons to flow through them easily. Therefore, insulators can be easily charged by friction as the extra electrons gained cannot escape easily. 

Electron affinity refers to the relative amount of love that a material has for electrons. If atoms of a material have high electron affinity, then that material will have relatively higher love for electrons. This property of electron affinity will be of utmost importance as we consider the common method of charging i.e, charging by friction or rubbing.

According to the definition of electrostatic induction, it is a redistribution of electrical charge in an object, caused by influence of nearby charges. In the presence of a charged body, an insulated conductor develops a positive charge on one end and a negative charge on other end. Such charges are called induced charges and the process is called electrostatic induction. 

It is one of the rule of charging by induction, that if the object is not grounded, the nearby charge will induce equal and opposite charges in the object. 

Whenever an induced charge is produced in an object, the charge spreads uniformly and distribute itself on its surface. 

Electrostatic induction is a redistribution of electrical charges in an object caused by the influence of nearby charges. Electrostatic generators such as the Wimshurst machine, the Vande Graph generator use this principle. 

When a charged $CD$ is brought near the paper snippets, opposite charge is induced on the paper snippets. As opposite charges attract, paper snippets are attracted by charged $CD$. So, this is an example of charging by induction. 

In case of charging by conduction, when an uncharged conductor is touched with a charged conductor, the uncharged conductor acquires charge similar to charged conductor. It happens because of the electrons are shared at the point of contact of the conductors. 

In both the methods, i.e, charging by friction and electrostatic conduction, the two bodies are brought in contact and sharing of electrons occurs at the point of contact. So, charging by friction can be explained by electrostatic conduction. 

When a piece of ebonite is rubbed with a piece of animal fur, frictional charging process results in a transfer of electrons between the two objects. Since ebonite has much greater attraction for electrons than animal fur (electron affinity). As a result, atoms of ebonite pull electrons from atoms of animal fur, and as a result, ebonite becomes negatively charged  and animal fur becomes positively charged.