Gauss’s Law And The Electric Field

Gauss’s Law and the Electric Field –  Previously, did Sinaumed’s know what electricity is, what are the uses of electricity, and what is the history of electricity? It’s a good idea to discuss these three things in this article. Let’s look at the short discussion!

Electricity is a condition of certain subatomic particles, such as electrons and protons, that cause attractive and repulsive forces between them. According to another understanding, electricity is a source of energy that can be channeled using cables. Electricity enables the creation of many well-known physical phenomena, such as lightning, electric currents and electric fields. Electricity can be used widely in various industrial applications such as for electric power sources and electronic devices.

Electricity gives rise to the four basic natural forces (gravity force, electromagnetism force, weak nuclear force and strong nuclear force). “Amount of electricity” is also known as “Electrical Charge” or “Total Charge”. There are two types of electric charges: positive and negative. Through experimentation, like-charges repel each other and opposite-sex charges attract one another.

When electricity flows through special materials, such as tungsten and tungsten, light is emitted by the metals. Such materials are used in light bulbs ( bulb or bulb). Whenever electricity flows through a material that has resistance, it releases heat energy. The greater the electric current, the more heat energy that arises will be multiplied. This property is used for electric stove elements, irons, and so on.

Electric current flows from positively charged channels to negatively charged channels. With direct current electricity, if Sinaumed’s only holds the positive cable (but doesn’t simultaneously hold the negative cable), the electricity will not flow to Sinaumed’s’ body (he will not be electrocuted). This also happens the other way around, like when Sinaumed’s only held negative channels.

Meanwhile, electricity that has alternating current, electricity can also flow to the floor of the house (or the earth). This can happen because it is caused by an electrical system that uses the earth as a reference for neutral voltage ( ground ). Therefore, if Sinaumed’s touches a power source and his feet are on the ground or his hands are touching a wall, electricity will flow from his hands to his feet and Sinaumed’s will get an electric shock (get an electric shock).

Electrical power can be stored, for example in a battery or accumulator. Small electric power, for example stored in a battery, will not have a shock effect on the body. Whereas in large car batteries, there is often a slight shock effect, although not too big and dangerous. Electricity will flow from the positive pole of the battery/battery to the negative pole.


Electricity cannot be separated from human life. Most of today’s human activities are highly dependent on electricity, both for primary and secondary needs. Electricity is also very useful in personal, social, trade, education, and various other lines of life. The needs of the trimmer, for example, are for the use of water pumps, cell phones , lighting devices, magic jars , electric irons, even today there are many vehicles that use electricity. Meanwhile, secondary needs, for example, are television, computers, educational media equipment, and so on.


History of the inventor of electricity there are several versions. The first version, electricity was discovered in ancient Egypt. The second version, Electricity was discovered by Thales from Melitus. And the third version, Electricity was discovered by Faraday.

First Version (Ancient Egyptian Period)

Theory, regarding electricity which was known and used during the heyday of Europe was wrong, it was the ancient Egyptians who discovered it and the Europeans only popularized it. The key to all of these theories lies a few hundred kilometers east of Egypt, in Iraq. There were some oddly shaped pots found. Some of these pots are waterproof and their contents are cylinders made of copper, and glued into the holes using bitumen. In the center of the cylinder is an iron rod. Researchers discovered the pot for the first time in 1936. Researchers believe that the pot is a galvanic element also known as a primitive battery. The reconstruction did show that it was possible to create electricity using these tools.

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It was discovered that next to a temple in the Dendera area, some tens of kilometers north of Luxor, experts discovered a light. An electrical engineer from Norway saw that the object shown in the relief at the top of this page could act as a lamp.

Second Version (Thales)

The early history of the discovery of electricity was carried out by a Greek scholar named Thales. Theles suggested that the phenomenon of amber, which when rubbed repeatedly would have the power to attract hairs, was an electrical phenomenon. Then, after many years since the idea from Thales was put forward, new opinions and various new theories about electricity emerged, as researched and advanced by William Gilbert, Oersted, Charles De Coulomb, Joseph Priestley, Ampere Michael Farraday, etc.

Third Version (Faraday)

Michael Faraday is a scientist from England and earned the nickname “Father of Electricity”, thanks to his efforts, electricity is now a technology that is widely used in human life. Faraday was born on September 22, 1791 in Newington, England. He studied various scientific fields, including electrochemistry and electromagnetism. Faraday also invented a device that was later used to become the Bunsen burner. The Bunsen burner is used in almost all science laboratories as a practical source of heat.

In order to help the family economy, at the age of 14 Faraday has worked as a salesman and book seller. In between his work, he uses his time to read various types of books, especially books on natural science, chemistry, and physics.

When he was 20 years old, Faraday attended various classes given by well-known British scientists. One of them is Sir Humphry Davy, a chemist who also works as head of the Royal Institution laboratory. During class, Faraday took careful notes and then neatly transcribed what he had heard.

Then, he sent the note file to Sir Humphry Davy accompanied by a job application attachment. It turned out that the lecturer was interested in appointing Faraday as his assistant at the famous University Laboratory in London. At that time Faraday was 21 years old.

Under Davy’s tutelage, Faraday displayed rapidly growing abilities. Initially, he was only given a job as a bottle washer. However, thanks to his persistence in learning, in a relatively short time, Faraday was able to make various kinds of new discoveries based on his own ideas, namely finding two chlorocarbon compounds and also succeeding in liquefying chlorine gas and several other types of gases. Thanks to his intelligence, Faraday was able to establish relationships with renowned experts, such as Andre Marie Ampere.

In addition, Faraday also had the opportunity to tour Europe with Davy. On this occasion, Faraday began to develop his practical and theoretical knowledge.

Davy was a great influence on Faraday’s thinking and had assisted Faraday in each of his discoveries. Faraday’s first highly influential discovery in the field of electricity occurred in 1821. Two years earlier Oersted had discovered that the magnetic needle of an ordinary compass could be tilted when an electric current was passed in a wire not too far apart. From these findings, Faraday concluded that when the magnet is tightened, what actually moves is the wire.

On the basis of this conjecture, Faraday managed to devise a clear scheme in which a wire would rotate continuously adjacent to a magnet as long as an electric current is applied to the wire.


The electric field is an effect caused by the presence of electric charges such as electrons and ions or protons in the space around them Judging from the understanding of the electric field, it can be exemplified by objects that have an electric charge. If object A which has an electric charge is placed in a space in which object B already exists.

If object B has an electric charge, then object A will also experience an electric force. The space around object A and object B is called an electric field. So, what is meant by an electric field (E) is a room that is around objects with electric charges that experience an electric force.
If an object that has an electric charge is placed in a room, then in that room there will be an electric field.

To describe an electric field, lines of electric force will be used. Lines of electric force are curved lines which are assumed to be the paths traversed by positive charges moving in an electric field. The lines of electric force cannot intersect, because the lines of electric force are an imaginary line that starts from an object with a positive charge and will end in an object with a negative charge. The following figure illustrates the lines of electric force around objects that contain electric charges.

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The electric field is described by lines of electric force whose direction starts from the positive pole to the negative pole.

Then how strong can an electric field affect an object? All depends on the magnitude of the source charge and the distance from the object (test charge). The electric field strength is formulated as the magnitude of the Coulomb force for each unit charge. Mathematically the electric field formula is:

E = electric field strength (N/C)
F = coulomb force (F)
q = test charge (C)

The direction of the electric field strength experienced by the test charge depends on the type of test charge and the source charge. If the charges are positive and negative, there will be an attractive force, but if the charges are the same, there will be a repulsive force.

When known by using the coulomb force formula between the source charge Q and the test charge q is

then the electric field formula becomes


Gauss’s law was created by Carl Fredrich (1777-1855), a mathematician of all time. Does Sinaumed’s know what Gauss’s law is? In general, we learn Gauss’s law at school in Physics lessons. In this section, we will discuss the meaning of Gauss’s law and its formula. Please listen to the explanation until it’s finished below.

Understanding Gauss’s Law

Gauss’s law is a law that states that the number of field lines that pass through a surface is proportional to the amount of charge that is on the surface. Gauss’s law relates the electric field that exists on a closed surface to the total charge inside that surface.

Gauss’s law is a law that is used to calculate the amount of an electric flux through a field. Gauss’s law states that the amount of electric flux through a field will be directly proportional.

The sound of Gauss’s Law, namely: “That the total electric flux passing through any closed surface (a surface that includes a certain volume) is proportional to the total (net) electric charge inside that surface”.

Gauss’s law is generally used to calculate the electric field that has been generated from very fast moving charges and also accelerated moving charges. Gauss’s law can be used to calculate the electric field of systems that have a high tendency of symmetry (eg cylindrical, square, and also spherical symmetries). In using Gauss Sinaumed’s law it is necessary to choose an imaginary closed surface (Gaussian surface). The shape of the closed surface can be anything.

Gauss’s law is based on the concept of electric field lines which have directions or arrows as shown in the following figure.



Fulk has a relationship to the magnitude of the field that penetrates in a direction perpendicular to a certain surface. Electric flux states that when an electric field penetrates in a direction perpendicular to a surface. It will be easier to illustrate when using a visual description of the electric field, namely the depiction of the electric field in the form of lines. By depicting the electric field (lines), the electric flux can be illustrated as the number of field “lines” that penetrate a surface. Come on, consider the following picture:

The following is the electric flux formula:

If the lines in the electric field that penetrate a plane have angles, then the electric flux formula is as follows.

Gauss’s Law Formula


Use of Gauss’s Law

If Sinaumed’s wants to apply Gauss’s law to determine how strong the electric field is around a charge distribution, it is necessary to pay attention to the following points.

  • What kind of symmetry does this system have, from the symmetry you will get a qualitative picture of the field.
  • Choose a (imaginary) surface which will be called a Gaussian surface according to the shape of the symmetry, passing through the point where you want to find out how strong the field is.
  • Correct selection of the Gaussian surface can produce E that is equal in size and perpendicular to some or all of the closed surface and zero to the other surfaces.

Gauss’s law on closed surfaces

Gauss’s law on the surface of the ball

Gauss’s Law Around Surfaces


Gauss’s law around a uniformly charged wire

Gauss’s law on a charged ball

The formula for an insulator ball that is evenly charged with a charge density is as follows:

Inside the ball, the equation is as follows:

Outside the ball, the equation is as follows: