Electric charge, Electric field, and Electric Dipole

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Electric charge is the property of substance that makes it possible for them to exact electric force or to respond to electric field.

Charges scalar quantity and its SI unit is Coulomb .

There are some basic properties of electric charge.

(i) Conservation of charge: The total charge of an isolated system is always conserved initial and final charge of the system will be same.

(ii) Quantization of charge: the charge on a body is always integral multiple of basic unit of charge .i.e. charge on an electron (e). This phenomena is called quantization of charge.

Magnitude of charge on a charged object q=±ne.

Here, n=number of electrons and e=charge on one electron.

                      q=±1e,±2e,±3e,............

Conductor and insulator: conductors are the material through which electric charge can flow easily . Insulator are the material through which electric charge cannot flow.

Force between two point charges: coulomb's law the force of attraction or repulsion between two point charges is determined by coulomb's law.

According to this law the force of interaction (attraction or repulsion) between two stationery point charges in vacuum or air is directly proportional to the product of the magnitude of charges (q1 and q2) and University proportional to the square of distance (r²) between them.

According to coulomb's law force between two charges.

                              F=Kq1q2/r²

Here, K is proportionality constant.

It's value is(1/4π€•)= 9×10⁹N-m²/C² 

                                &

 €• =permittivity of free space or vacuum, it's value is 8.85×10¹² C²/N-m².

IF THE MEDIUM BETWEEN THE CHARGE IS OTHER THAN AIR THEN THE VALUE OF COULOMB'S FORCE 

                         [F=1/4π × q1q2/r²]

If dielectric constants of the medium between the charge is K.  

                           [F=1/4πK × q1q2/r²]

In vector form, [ F=1/4π€•×q1q2r^/r²]

Here,r^ is a unit vector along r. 

Force between multiple charges: principle of superposition .This principle states that the net electric force experienced by a given charge particle q0 due two a system of charged particle is equal to the vector some of all the forces exerated on it due to all the other charged particle of the system.                 

               [F=F1+F2+F3+F4.........+Fn]

Electrostatic force due to continuous charge distribution: The reason in which charges are closed spaced is said to have continuous distribution of charge.

Electric field: The electric field due to a charge Q is defined as the reason around it in which a unit positive charge wood experience a force if it is placed at a point in that field.

Intensity of electric field: The the electric field intensity (E) add any point due to a source charge is defined as the force (F) experienced per unit positive test charge (q0) at that point.

[Intensity of electric field ,E=F/q0.]

Electric field intensity is a vector quantity. It's SI unit is Newton per Coulomb or volt per metre .

•The for supplied on any charge due to electric field is direction of force on a negative charge is awarded to the direction of electric field and direction of force on positive charge is along the direction of electric field.

•electric field intensity due to a point charge q at a distance are from it in a medium is

                      [E=1/4π€•K(q/r²)]

Where, K= dielectric constant of the medium.

Electric field due to a system of charge is:

Same as the case of electrostatic force, here we will apply principal of superposition.

             [E=E1+E2+E3........+En]

Electric field lines:

Electric field lines are away of victorially mapping the electric field around a configuration of charge . These line start from positive charge and end on negative charge . The president on the lines at any point give the direction of electric field at that point.

Electric dipole: An electric dipole is a system found by two equal and opposite point charges placed at a short distance apart. Ex. HCL,CH4,HBr,H2O etc.

Electric dipole moment: The product of the magnitude of either charge and distance between two charges is called electric dipole moment.

Let,q is a magnitude of either charge of electric dipole and d is a distance between the t

wo charges, then electric dipole moment .    

                [p=qd]