Charging by Induction Class 12 Notes | EduRev

Physics Class 12

Class 12 : Charging by Induction Class 12 Notes | EduRev

The document Charging by Induction Class 12 Notes | EduRev is a part of the Class 12 Course Physics Class 12.
All you need of Class 12 at this link: Class 12

Most objects are electrically neutral, which means that they have an equal number of positive and negative charges. In order to charge an object, one has to alter the charge balance of positive and negative charges. There are three ways to do it: friction, conduction and induction.


Charging by Friction

The charging by friction process involves rubbing of one particle on another resulting in electrons moving from one surface to another. This method is useful for charging insulators.

Charging by Induction Class 12 Notes | EduRev


Charging by Conduction

The charging by conduction process involves touching of a charged particle to a conductive material. This way, the charges are transferred from the charged material to the conductor. This method is useful for charging conductors.


Charging By Induction

  • Charging by induction occurs when we bring a charged object near a conductor. It is not for no reasons that we say near.
  • The charged object does not actually touch the conductor. The charged object is just allowed to get close to the conductor.
  • As a result, the conductor will be charged. We say that a charge has been induced in the conductor. We will make this clear with an experiment.

ExperimentCharging by Induction Class 12 Notes | EduRev

  • Consider the two spheres above made with a metal. 
  • Since metal is a good conductor, it is a good choice for this experiment.
    (i) They touch each other, so they become a single conductor.
    (ii) We put them on insulated stands so charges or electricity does not travel to the ground.
    (iii) The two spheres right now form a neutral system. This means that there is the same number of electrons and protons in each sphere.
  • We get a rod that is negatively charged and we put it next to the two spheres. The rod is shown on the right in green. The lines inside the rod represent negative charges.Charging by Induction Class 12 Notes | EduRev
  • Electrons in sphere B are repelled by the rod and move to sphere A to create an excessive charge called also net charge. This situation creates also a net charge in sphere B.
  • We say that a charge has been induced on the spheres.
  • We can separate the spheres while the rod is still there.Charging by Induction Class 12 Notes | EduRev
  • Finally, we can remove the rod completely.

Charging by Induction Class 12 Notes | EduRev

  • The spheres will keep their charges and this is what we mean by charging by induction.
  • The charges on the spheres are equal and opposite.
  • The charges are equal because for each single electron that goes to A and therefore creates a single negative net charge, it leaves B with a single positive charge.

In our example above, 3 electrons went to A creating a situation where B has a positive charge with 3 protons.

Keep in mind that spheres A and B could have billions and billions of electrons. The reason that sphere A is charged now is because it has an excess of 3 electrons although this is a small charge. By the same token, the reason sphere B is charged is because it has 3 more protons now than electrons.

Charging by induction and grounding Use only 1 sphere this time and induce a charge again with a charged rod. Then, put your finger where the electrons are.

Charging by Induction Class 12 Notes | EduRevWhen you touch the metal with your finger, electrons leave the sphere by means of your finger and enter the ground.

Charging by Induction Class 12 Notes | EduRevWhen we allow charges or electricity to leave a conductor by touching it, we are grounding the conductor.

Offer running on EduRev: Apply code STAYHOME200 to get INR 200 off on our premium plan EduRev Infinity!

Related Searches

Charging by Induction Class 12 Notes | EduRev

,

Exam

,

video lectures

,

Charging by Induction Class 12 Notes | EduRev

,

mock tests for examination

,

ppt

,

Summary

,

pdf

,

Previous Year Questions with Solutions

,

Charging by Induction Class 12 Notes | EduRev

,

Objective type Questions

,

MCQs

,

study material

,

Semester Notes

,

shortcuts and tricks

,

Important questions

,

Free

,

Extra Questions

,

past year papers

,

Viva Questions

,

Sample Paper

,

practice quizzes

;