Electric Dipole

Electric Dipole

Dipole- A distance between two equal and oppositely charged or magnetised poles.What is electric dipole ? Or define electric dipole or definition of electric dipole:-A pair of opposite charges q and –q separated by a distance d is called an electric dipole. Electric dipoles in space always point from negative charge -q to positive charge q by default. The dipole's center is defined as the point where q and –q meet. A pair of electric charges with opposite signs and equal magnitude separated by distance is the simplest example of an electric dipole.

(Electric dipole field of two point charges)

There are two types of dipoles in electromagnetism: In every electromagnetic system, an electric dipole is used to separate the positive and negative charges. A pair of electric charges of equal magnitude but opposite sign separated by a typically small distance is a simple example of this system.

Also read -

  • NCERT Solutions for Class 11 Physics
  • NCERT Solutions for Class 12 Physics
  • NCERT Solutions for All Subjects

Electric Dipole Visualization-

Assume there are two equal-sized charges, ‘q,' separated by a distance, d. An electric dipole is the name given to this configuration. As a result, we can state that an electric dipole is formed by a separation of a specific distance between equal and opposite charges.

The symbol p stands for an electric dipole. The product of the magnitude of the charges multiplied by the distance between them is known as an electric dipole, and it may be mathematically stated as follows:

An electric dipole's magnitude is expressed as ,

p = Qd.

Direction of electric dipole moment-

The electric dipole moment is a vector quantity with a definite direction of travel from negative to positive charge. It's vital to remember, however, that this orientation norm is solely followed in Physics. In chemistry, the convention is that the polarity should be reversed, from positive to negative. The axis of the dipole is the line that runs along the direction of an electric dipole.

Electric potential due to dipole-

The dipole moment of an electric dipole is given by the formula P=2qa. V=Kqr denotes the electric potential owing to a charge q at a position r away from the charge, where V denotes the charge's potential and K denotes the permittivity of free space.

Due to a Dipole, there is an electric potential (V)

Assume that a dipole is formed by two charges, –q at A and +q at B, separated by a distance d. Assume that O is the midpoint of AB.

At every location P where OP = r, the electric potential due to a dipole will be:

V= 1 P cosθ

4πϵ r^2

If = 90°, this is the first case.

V = 0 is the electric potential.

Case 2: If is equal to 0°

V= 1 P

4πϵ r^2

= electric potential

Electric dipole formula-

For a pair of equal and opposing charges, the formula for electric dipole moment is p = qd, where qd is the magnitude of the charges multiplied by the distance between them.

Electric dipole moment / electric dipole unit-

The electric dipole moment is a measurement of a system's overall polarity, or the separation of positive and negative electrical charges inside it. The coulomb-meter (Cm) is the SI unit for electric dipole moment; nevertheless, the debye is a regularly used unit in atomic physics and chemistry (D).

Example of electric dipole-

A pair of electric charges with opposite signs and equal magnitude separated by distance is the simplest example of an electric dipole.

Force between two dipoles-

The potential energy of two electric dipoles determines the force operating between them. Because the charges are pushed equally and oppositely when the dipole moment is constant, the net force is zero.

Dipole’s physical importance that is its significance-

The electric dipole is important in both electrostatics and chemistry. Because the centres of positive and negative charges in most molecules occur at the same place, the distance between two charges is zero. Carbon dioxide and methane belong to the zero dipole moment category. Non-polar molecules are the name for this sort of molecule. Polar molecules are those that have a persistent dipole moment because the centres of positive and negative charge do not coincide.

Also check-

  • NCERT Exemplar Class 11th Physics Solutions
  • NCERT Exemplar Class 12th Physics Solutions
  • NCERT Exemplar Solutions for All Subjects