An interesting way to electrically charge an object without making direct contact is by induction charging. It is based on the idea that surrounding charged objects have the power to redistribute electric charges within a conductor. This idea is fundamental to understanding how electric fields behave and is used extensively in devices like touch screens, electrostatic precipitators, and capacitors.
Charging by Induction
The process of charging a neutral body by bringing a charged body near it without making actual contact between the two bodies is known as charging by induction.
Principle Behind Charging by Induction
The flow of electrons within a conductor is the fundamental concept underlying charging via induction. The electric field of the charged object pushes against the free electrons in the conductor when it is brought close to a neutral conductor.
Consequently, depending on the type of external charge, electrons either migrate toward or away from the side closest to the charged item.
When the conductor‘s electrons are drawn to a positively charged external object, they gather on the side nearest to the external charge. Electrons are repelled and migrate to the side that is most far from the external charge if the object is negatively charged.
Although the conductor is electrically neutral overall, this charge redistribution separates the positive and negative charges within the conductor.
Process of Charging by Induction
Process of Charging by Induction
Several vital processes are involved in the full induction charging process of a conductor:
1. Bringing the Charged Object Close: A charged object is brought near the conductor without making contact with it. The electric field of the external charge creates an unequal distribution of charges because of this closeness.
2. Grounding the Conductor: Next, a conducting wire is used to temporarily link the conductor to the ground, or Earth. Depending on the impact of the external charge, grounding permits free electrons to move into or out of the conductor.
Electrons move from the Earth into the conductor if the external charge is positive.
When there is a negative external charge, electrons move from the conductor to the Earth.
3. Cutting the Ground Connection: The ground connection is cut whenever enough charge has moved. By doing this, the induced charges are guaranteed to stay on the conductor.
Eliminating the External Charge: At last, the externally charged item is taken out. At this point, the conductor’s net charge is opposite in sign to the inducing object’s.
Therefore, without ever coming into direct contact with the charged body, a conductor can be permanently charged through induction.
Important Characteristics of Charging by Induction
No Contact Is Necessary: The charged object and the object being charged never make physical contact.
Conservation of Charge: The system’s overall charge is kept constant. The conductor’s gain or loss of charge originates in or exits the Earth.
Opposing Nature of Induced Charge: The conductor’s ultimate charge is invariably opposing to the charged body that is causing it.
Earthing’s Function: During the induction process, grounding is necessary to either feed or drain the charges.
Applications of Charging by Induction
Industries use electrostatic precipitators to filter smoke and dust particles out of gasses.
Capacitors: Capacitors store energy in an electric field by using induction.
Induction charging aids in drawing toner particles to paper in photocopiers and laser printers.
Lightning Rods: During thunderstorms, induction assists in the safe release of excess charges from buildings.
