What is Electric Field Strength or Electric Field Intensity?

Electric Field Strength and Electric Field Intensity Definition

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What is electric field strength or electric field intensity? Electric Field Strength or Electric Field Intensity definition: is the synonym of electric field. Or Electric Field Strength or Electric Field Intensity definition: the force acting on a unit positive charge inside an electric field is termed as electric field strength or electric field intensity.

Electric intensity is the strength of electric field at a point. Electric intensity at a point is defined as the force experienced. per unit positive charge at a point placed in the electric field.

Electric field strength is a quantitative expression of the intensity of an electric field at a particular location. The standard unit is the volt per meter (v/m or v · m -1). A field strength of 1 v/m represents a potential difference of one volt between points separated by one meter.

Electric Field Strength and Electric Field Intensity Definition

Electric field strength can be determined by Coulomb’s law. According to this law, the force ‘F’ between two point charges having charge Q1 and Q2 Coulombs and placed at a distance d meter from each other is given by:

Coulomb’s law

Here, εo is the permittivity of vacuum = 8.854 × 10 – 12 F/m and εr is the relative permittivity of the surrounding medium.

Now, let us put Q2 = + 1 Coulomb and let us denote force F by E in the equation (1), and by doing these we get:

This equation shows the force acting the a unit positive charge placed at a distance d from charge Q1.

electric field

As per definition, this is nothing but of electric field strength of charge Q1 at a distance d from that charge. Now, we got the expression of electric field strength or intensity. Now, by combining this expression with equation (1), we get:

Electric Field Strength or Electric Field Intensity in Newton / Coulomb

The above expression shows that, if we place a charge at any point in an electric field, the product of the electric field strength at that point and the charge of the body gives the force acting on the body at that point in the field. The above expression can also be rewritten as:

Depending on this expression, the electric field strength can be expressed in Newton / Coulomb. That is unit of electric field strength is Newton / Coulomb.

The electric field strength has direction and hence it is a vector quantity. Intensity means the magnitude or amount. Now field intensity similarly means the magnitude of the strength of the field. Finally electric field intensity or strength can be written as:

So far we have discussed the electric field intensity at a point due to the influence of a single charge, but there may be a case where the point is under the filed of many charged bodies.

In that case, we first have to calculate, the electric field strength at that point for individual charges and then we have to vectorially add up all the field strengths to get resultant field strength at that point.

Electric Field Strength or Electric Field Intensity Conclusion

After going through the above portion of electric field strength or electric field intensity we can now establish electric field strength or electric field intensity definition. I hope you enjoy when reading this article, thank you.