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Superposition principle

Electrostatics follow various laws. The superposition principle in Electrostatics is all about the superposition of charges which decides the exact force of the charge.

The superposition principle of electric charges is very similar to the superposition of waves. Force on a specific charge due to another charge under an electric field’s influence cannot be calculated as the scalar sum. On the other hand, It would be the excess of these forces that takes place.

The most famous example of the superposition principle is drawing a triangle and placing three different charges at the triangle’s vertices. The force produced at the midpoint of the triangle would be the vector sum of all the three different charges. The direction of the resultant force will be opposite or towards the heaviest charge in the triangle.

Continuous Charge Distribution

The concept of continuous charge distribution is also something very new and strange in electric fields. To help you understand, it is a system with a continuous charge distribution. The main factor is that this charge will be uniformly distributed throughout the conductor without changing the time.

There could be different types of charge distributions.

  • Line charge distribution
  • Surface charge distribution
  • Volume charge distribution

Line charge- When we talk of line charge, you must know that it is distributed evenly or non evenly over a straight line. The charge distribution in such a case is effortless and straightforward.

Surface charge- the surface charge is mainly applicable to the Gaussian bodies. According to the rule, the surface charge will apply to the surface of any spherical or body that has a well-defined boundary.

Volume charge- volume charges are also basically the same as that defined on a surface charge. It is the charge distributed to the entire volume of an enclosed body.

The calculation of electric fields in these bodies could be calculated by a particular theorem called the Gauss theorem

Gauss law

Gauss Law defines that a closed surface’s ultimate electric flux is proportional to its enclosed charge. Later, with the permittivity value it is divided.

Gauss law is only applicable to Gaussian bodies. It is a simple law that can help solve different electrostatic problems in symmetries and unsymmetrical bodies such as cylindrical, spheres, and even irregular intervention bodies.

Gauss law works on specific electric flux contained inside a closed surface.

Linear charge distribution

When the charge is uniformly or non uniformly distributed across a linear body or over the length of the conductor, it could be called a linear charge distribution.

There could be various methodologies and formulas related to this distribution, but to simplify it for you, it is often denoted as the symbol lambda.

The linear charge distribution is directly proportional to the change in the small unit of charge and inversely proportional to the change in the length.

Surface charge density

Similar to the linear charge distribution, you can also get a surface charge distribution often denoted by the symbol Sigma. Charge denotes the uniform distribution of the charge over the conductor’s surface. Similar to the linear charge distribution, it is also directly proportional to the change in the charge and is indirectly proportional to the change in the small area where the charge distribution is seen.

Volume charge distribution

When a certain amount of charge is distributed across the volume of the specific body, it is known as volume charge distribution. Such distribution code takes place inside a sphere or a cylindrical and is measured in Coulomb per cubic meters.

Principle of superposition in electrostatic

The principle of superposition in conductors has specific characteristics and rules that need to be followed for getting an accurate result. We have mentioned some of them down here –

  • The resultant force will always be the vector sum addition. A charge is a vector property, and if you want to get the resultant force, all you need is the proper orientation and the addition of charges in a specific way.
  • On the other hand, the direction of the charge on the resultant force becomes a significant factor in the superposition principle. If the charge that contains the highest value is donating its force to the right side, then the resultant force, according to the superposition principle, will also act on the right side.
  • The superposition principle is also applied when the masses are in motion. The relative velocity could be taken in if the masses are in motion. Hence, it has to apply in the charge function, but you need to remember that there won’t be any addition of the velocity factor in the force unit.

Applications

The superposition’s applicability According to the theorem, we can only use linear circuits and circuits with additional supplies. Calculating equivalent section currents and voltages involves figuring out what they’ll do with each power supply in use.

Conclusion

In electrostatics, the concept of superposition for charges may be used to compute the force acting on them. The charge distribution on those particles is also covered in three separate methods. As a result, all of the variables, such as wavelength, frequency, force, and form, are quantifiable and significant.

faq

Frequently asked questions

Get answers to the most common queries related to the NEET UG Examination Preparation.

Is it possible to apply the superposition theorem to non-linear circuits?

Ans – The superposition theorem is only applicable to non-linear circuits.

Two principles on which the superposition theorem is based.

Ans – The assumption of linearity between the response and excitation of an electrical circui...Read full

Why can't we use superposition for voltage?

Ans – Voltage and current can be superimposed, but not power. To compute power, we first calc...Read full

What happens if the charge starts to move?

Ans – The superposition law will still be maintained if the charge gets a specific motion in ...Read full

What does superposition imply regarding direction?

Ans – The superposition principle tells us how the resultant will get oriented. The resultant force will be oriented where t...Read full

What is volumetric charge distribution?

Ans – The volumetric charge distribution is the charge distribution over a given volume. It c...Read full