Table of Contents
Charging of Insulators
Since charge cannot flow through insulators, neither conduction nor induction can be used to charge, insulators, so in order to charge an insulator friction is used. Whenever an insulator is rubbed against a body exchange of electrons takes place between the two. This results in appearance of equal and opposite charges on the insulator and the other body. Thus the insulator is charged.
For example rubbing of plastic with fur, silk with glass causes charging of these things.
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COULOMB’S LAW
Last modified on:3 years agoReading Time:18MinutesCOULOMB’S LAW: Two point electric charges q1 and q2 at rest, separated by a distance r exert a force on each other whose magnitude is given by If between the two charges there is free space then Where ε0 is the absolute electric permittivity of the free space and ε0 =…
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If we comb our hair on a dry day and bring the comb near small pieces of paper, the comb attracts the pieces, why?
Last modified on:4 years agoReading Time:2Minutes If we comb our hair on a dry day and bring the comb near small pieces of paper, the comb attracts the pieces, why? Answer: This is an example of frictional electricity and induction. When we comb our hair, it gets positively charged by rubbing. When the comb is brought…
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Can two similarly charged bodies attract each other?
Last modified on:4 years agoReading Time:1Minute Yes, when the charge on one body Q is much greater than that on the other q and they are close enough to each other so that force of attraction between Q and induced charge on the other exceeds the force of repulsion between Q and q. However, two similar…
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Physics MCQs for Class 12 with Answers Semiconductor Electronics
Last modified on:5 years agoReading Time:31MinutesQ.1. In a semiconductor(a) there are no free electrons at 0 K(b) there are no free electrons at any temperature(c) the number of free electrons increases with pressure(d) the number of free electrons is more than that in a conductor Answer Answer: (a) Q.2. Let nh and ne be the number…
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Electric Charges and Fields Class 12 Physics MCQ Questions
Last modified on:2 years agoReading Time:38MinutesHere we are providing mcq questions for class 12 physics chapter 1 electric charges and fields. Students are suggested to go through each and every question to perform better in exams. Chapter Electric Charges and Fields Type of Questions MCQ Nature of Questions Competency Based Questions Board CBSE Class 12 Subject…
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Class 11 Chemistry Ch-8 Redox Reactions (VSQ)
Last modified on:5 years agoReading Time:9MinutesQ.1. Identify the oxidizing agent and the reducing agent in the following reaction H2S + HNO3 → NO + S + H2O Answer Answer: In the reaction HNO3 is an oxidizing agent since it itself gets reduced from +5 to +2. While H2S is an reducing agent since it itself gets…
