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Calculating the Value of an Electric Field

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Electricity - Calculating the Value of an Electric Field

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Electricity is one of the critical topics in the field of physics. It is also important in our day-to-day lives. While gaining sound knowledge on electricity, several new Concepts have come across like the electric field, magnetic field, electrons, protons, etc., and many more. Among all those topics, learn and understand about the electric field. Also, know how to calculate the value of an electric field?

Electric Field Definition

The electric field is a field in which each point of the field has either a positive charge or negative charge by exerting some force. As every item consists of both charges in the form of a nucleus and electrons, they attract or repel with other particles of an atom. This process can be done either through electric fields or through magnetic fields.

How to Calculate the Value of an Electric Field

For calculating the value of an electric field, different formulas are available based on the requirement. 

If the value is required in terms of charge point and distance, 

E= K*(Q/r2)

Derivation

To derive the formula for the electric field, let's recall Coulomb's law of equations.

According to Coulomb's law, the electric force existing between two different charges is always directly proportional to the product of these two charges and inversely proportional to the square of the distance between those two charges. 

Let us assume that Q, q are two different charges. Where capital Q is the source charge and q is the test charge. And r is the distance between those two charges. Applying these variables in Coulomb's law in the formula of electric force we get,

F = K(Q*q)/r2

As we know that the magnitude of an electric field is defined as the force per charge, 

E = F/q

Here the charge can be taken as a test charge.

Now substitute the force formula in the electric field formula.

E =K [(Q*q)/r2]/q

Then the test charge will be canceled from the numerator and denominator.

Hence the obtained formula for the magnitude of electric field E is,

E = K*(Q/r2)

Where,

        E is the magnitude of an electric field,

        K is Coulomb's constant

        Q is the charge point,

        r is the distance from the point,

Similarly, if we need to calculate the value of an electric field in terms of electric potential, the formula is,

E= - grade.

It is a vector calculus notation. According to the definition of an electric field, it is always equal to the negative gradient of electric potential. By considering this definition, the above formula was derived.

Concerning the given data, it is easy to calculate the value of the electric field in terms of distance and the charge as well as electric potential. Both of these formulae were used to solve physics word problems also.

Units and Direction of Electric Field

The magnitude of electric field E is measured in terms of Volts per meter, an SI system unit.

The direction of the electric field will be outwards for positively charged particles and inwards for negatively charged particles. Usually, it flows in the direction of a positive charge.

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Using Gauss law

Let's see how to calculate the value of an electric field using Gauss law. The procedure is simple and straightforward with few steps.

  • First, we need to find a spatial symmetry that may be either spherical, linear circular, etc. for charge distribution.

  • Next, take a gaussian symmetry which is similar to that of the spatial symmetry.

  •  Let's find integral \[\varphi\] SE and then flux.

  • Now the charge is enclosed by the whole surface.

  • Let's find that electric field using formulae which may vary by the shape of the spatial symmetry. 

Conclusion

Hence, the electric field is a charge distributed to each point of the field by exerting some force on both positive and negative particles. It can be determined and calculated by various factors. Also, it has various specifications in terms of deriving formulas in different cases. The magnitude of the electric field is measured using Volts per meter. The electric potential, charge distribution, distance between two charges, etc. were considered a major league. The electric field can be calculated at a single point to charge and the charge between two or more points.

FAQ (Frequently Asked Questions)

1. What are the Properties of an Electric Field?

A. The electric field has various properties. They are as follows- 

  • The lines of electric fields never intersect each other.

  • The lines are completely perpendicular to the surface charge.

  • If lines are close to each other, the electric field is strong. If the lines are distant from each other, the electric field is weak as it is inversely proportional to distance.

  • The flow of the electric field starts from positive charge to negative charge.

  • The number of lines in the electric field depends on the magnitude of the surface.

  • The electric charge is continuous if curved lines are observed.

These are the various properties of the electric field.

2. What is an Electric Field, and What are its Types?

A. The electric field is a property where every point is charged by electricity, whether by repelling or attracting electrons. The nucleus is a negatively charged particle. It is directly proportional to the product of those two charges and inversely proportional to the square of the distance between those two charges. Its SI unit is either Newton per Coulomb or Volt per meter.

The different types of electric field were explained as follows- 


Uniform Electric Field:-  

When the electric field calculated at any point in the whole field is the same, then that electric field is known as the uniform Electric field. That means the charge distribution had been done uniformly. 


Nonuniform Electric Field:-  

If the charge was not distributed uniformly, then the electric field is a nonuniform Electric field hitch. This means the value of the electric field is different from one point to another point.