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.
-
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 =…
-
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…
-
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…
-
Important Derivations for Class 12 Physics Chapter 7 Alternating Current
Last modified on:3 years agoReading Time:12MinutesImportant Derivations for Class 12 Physics Chapter 7 Alternating Current Derivations Related to A.C. Applied Across an Inductor Derivation 1: (1) An ac voltage, V = V0 sin wt, is applied across a pure inductor L. Obtain an expression for the current I in the circuit and hence obtain the(i) inductive…
-
Important Derivations for Class 12 Physics Chapter 1 Electric Charges and Fields
Last modified on:3 years agoReading Time:15MinutesImportant Derivations for Class 12 Physics Chapter 1 Electric Charges and Fields Q.1. Using Gauss’s law, prove that the electric field at a point due to a uniformly charged infinite plane sheet is independent of the distance from it. Solution: Q.2. Derive an expression for the torque experienced by an electric…
-
Problems Based on Equation of SHM for JEE Physics
Last modified on:3 years agoReading Time:8MinutesEquation of SHM Velocity in SHM Acceleration in SHM Q.1. Prove that y = Aeiωt is an equation of SHM. Solution:
