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Physical Significance of Electric Field

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Description and Significance of Electric Field

An electric field that we are already aware of is said to be an elegant way of characterizing the electrical environment of a system of charges. The electric field said to be at any point in space around a system of charges represents the force of a unit positive test charge which generally would experience if placed at that point. The term field that we have learned in the subject in physics generally refers to a quantity defined at every point in space and may vary from point to point.


It's the physical field that surrounds charged particles and has an effect on all other charged particles in the field, either attracting them or repelling them. 


Electric fields are produced by electric charges or by magnetic fields that vary over time. The electric field, for example, is the attractive force that holds the atomic nucleus and electrons together in atoms in atomic physics and chemistry.


Additionally, it is the force that is responsible for the chemical bonding of atoms to form molecules.


This means that the electric field around a system of charges shows how much force a positive test charge would get if it were placed there. 


Most of the time, the term field means something that is the same at every point in space and can change from one place to another. 


Because force is a vector, the electric field is a vector field, which means it moves in the same direction.


Detailed Description of Electric Field

The electric field which we have seen is said to be defined at each point in space as the force per unit charge that would be experienced by a vanishingly small positive test charge held at that point. The vector fields of this form are sometimes referred to as force fields. This is said to be the basis for the law of Coulomb's which states that for stationary charges the electric field varies with the source charge and is said to be inverse with the square of the distance from the source. 


This means that if the source the charge which was doubled then the electric field would double and after doubling we see that if we move twice as far away from the source the field at that point would be only one-quarter its original strength.


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The electric field w can be visualized with a set of lines whose direction at each point is the same as the field's, a concept introduced by Michael Faraday whose term 'lines of force' is still sometimes used. Then we can see that the field lines are the paths that a point positive charge would follow as it is forced to move within the field that is said to be similar to trajectories that masses follow within a gravitational field.


Physical Significance of Electric Field

Under Static Condition

An electric field describes the electrical environment around a system of charges when they are in a stable state. It is defined at each location and differs from one to the next.


Non-Static Electromagnetic Condition

The accelerated motion of the charge causes electromagnetic waves to travel with a speed of c and exert a force on another charge in this situation. The transport of energy is linked to time-dependent magnetic and electric fields.


The electric field is a feature of a charging system that is independent of the test charge. Charge interaction is electromagnetic.


When dealing with time-dependent electromagnetic phenomena, the actual physical signs of the electric field appear.


Consider the accelerated motion of two distant charges, q1 and q2. The effect of q1 motion on q2 does not appear immediately. Between the effect and the cause, there will be a time delay. The electric field accounts for this time delay as follows: Electromagnetic waves are produced by q1's accelerated velocity. These waves travel at c, reaching the charge q2 and exerting a force on it. This explains the time difference.


Electric and magnetic fields are viewed as tangible entities, not just mathematical constructions, even though they can only be identified through their effects (forces) on charges. 


They have their dynamics, in other words, they evolve according to their own set of rules. 


They also can carry energy. As a result, a source of time-dependent electromagnetic fields that are turned on and off briefly leaves energy-carrying back-propagating electromagnetic fields. 


Faraday was the first to establish the concept of the field, which is now one of the most important concepts in physics.


Conclusion

This is all about the significance of an electric field in different conditions. Follow the concepts clearly and understand how an electric field behaves in different conditions. 

FAQs on Physical Significance of Electric Field

1. Is it possible to have an electric field without charged particles?

Yes, electromagnetic fields can occur in the absence of charged particles. In the absence of charges, these are the so-called vacuum solutions of Maxwell's field equations, which are nontrivial solutions. 


Plane waves of different frequencies, including light beams, are the solutions.


However, if you add the boundary constraint that the electromagnetic field must vanish at infinity, you're left with only one option: no electromagnetic fields in the absence of charges. 


There must be charged particles if that ray of light doesn't come from somewhere else.

2. What are electric field lines and their properties?

An imaginary line or curve drawn from a location of an electric field such that tangent to it (at any point) gives the direction of the electric field at that point is known as an electric field line.

  • Electric field lines begin with a positive charge and end with a negative charge.

  • The number of field lines that begin and finish at a charge is proportional to the charge's magnitude.

3. Are electric field lines straight?

It is possible to have an even distribution of field lines in a homogeneous electric field because they are straight, parallel, and evenly spaced. 


Electric field lines can’t create closed loops because the lines can never begin and terminate on the same charge. Whenever possible, these field lines flow from a higher potential to a lower potential.


If two lines intersect at any point, two tangents can be drawn at that point, indicating two directions of the electric field, which is not conceivable because each point has only one direction of the field.


As a result, they never cross paths with one another.

4. What are Electric Field Lines Attraction and Repulsion?

Field lines in electric fields always point away from a positive charge and in the direction of a negative point. In actuality, electric fields begin with a positive charge and end with a negative charge, as the name implies. 


When it comes to visualizing electric fields, field lines are extremely useful. Almost as if they are attempting to push each other away, you can feel the attraction between unlike charges and the repulsion between similar charges.

5. What are the examples of the Electric field?

Electric Lamps: When an electric lamp is connected to a power source via an electric connection, it can generate electric fields in the air around it. The electric field's intensity increases as the voltage rises. 

Voltage can exist even if there is no active electric current because an electric field can be formed around an electrical appliance without it being turned on.


Antennas for transmitting and receiving radio and television signals: A message is transmitted from a radio station's transmitting device to a common radio via an electric field formed by antennas that capture and transmit the data. 


A metal rod is the most prevalent shape. Each radio station operates at a specific frequency, which generates different electric fields. 


The operation is based on the periodic movement of electric energy charges, which move from one end to the other, generating an excess of negative charge at one end of the antenna and a positive charge deficit at the other end, and are exchanged from one end to the other, generating polarity.