Electricity and magnetism form an inseparable duo behind many of the fundamental technological innovations of our modern society. Understanding this profound relationship between two seemingly different forces is crucial for a wide range of applications, from energy production to communications and medicine. From generating electricity from renewable sources to designing ultra-efficient electric motors, this interconnectedness is revolutionizing the way we live and interact with the world around us. In this article you will explore and delve into the basics of the relationship between electricity and magnetism, as well as how they interact to power modern technology.

What is the difference between electricity and magnetism?

Definition of electricity

Electricity is a form of energy resulting from the movement of charged particles, called  electrons , across a conductor. It is generated from various sources, such as power plants, batteries, and solar panels. When an electrical circuit is closed, electrons move in an orderly manner, causing current to flow. Electricity is essential for a wide range of applications, from lighting our homes to modern communications systems to the electric motors that power our appliances.

Definition of magnetism

Magnetism is a natural physical force that occurs when matter affects moving charged particles. Magnets, for example, are materials that generate a magnetic field. They have two poles, north and south, that attract or repel each other depending on their direction. Magnetism is ubiquitous in our daily lives, from compasses that indicate true north to modern technologies like hard drives and speakers that exploit magnetic properties to work.

What is the relationship between electricity and magnetism?

These three following ideas form the foundations for understanding the relationship between electricity and magnetism, and have broad and diverse implications for our daily use of energy and technology.

a. Electric currents and magnetic fields

Magnetic fields are generated as a result of the movement of electrical charges. When electrons move through a conducting wire, they create a magnetic field around them. This is called an induced magnetic field. This fundamental discovery was highlighted by experiments such as the Ampere experiment, which showed that electrical currents could affect a compass needle. This revolutionary observation demonstrated the inextricable relationship between electricity and magnetism, and thus laid the foundation for modern electromagnetism.

B. Oersted effect and current on magnets

Ørsted’s experiment was a crucial advance in understanding the interaction between electricity and magnetism. By observing that an electric current could deflect a compass, Ørsted showed that the magnetic field surrounding a conducting wire changed in the presence of an electric current. This discovery paved the way for the design of devices such as electric motors, which exploit this interaction to convert electrical energy into mechanical motion. In addition, it also led to the development of magnetic switches, which are essential components in many electrical circuits.

C. Laws of electromagnetism

The laws of electromagnetism ( Faraday’s Law and Ampere’s Law ) provide the mathematical foundations for describing the interactions between electric and magnetic fields. Faraday’s Law states the principle of electromagnetic induction, explaining that a changing magnetic field in a circuit generates an electromotive force and generates an electric current. This law is the basis of devices such as electric generators. On the other hand, Ampere’s law determines the magnetic field generated by an electric current. It is crucial in the design of devices such as electrical transformers, which exploit differences in magnetic fields to convert and distribute electrical energy.

Practical applications between electricity and magnetism

The following three practical applications illustrate how the relationship between electricity and magnetism underpins the fundamental technologies that support our daily lives and modern industry.

a. Electric motors

Electric motors are one of the most widespread applications of the relationship between electricity and magnetism. It works on the principle of interaction between magnetic fields and electric currents. Inside an electric motor, an electric current is applied to coils of conducting wire placed within a magnetic field generated by a permanent magnet or an electromagnet. This magnetic field affects the moving electrical charges, causing the motor shaft to rotate. This conversion of electrical energy into mechanical energy can power a wide range of devices and systems, from industrial fans to electric cars to machine tools.

B. Electrical generators

Electric generators work on the reverse principle of electric motors. They convert mechanical energy into electrical energy by exploiting electromagnetic induction, a fundamental property discovered by Faraday. When a conductor moves through a magnetic field, it generates an electric current. Generators use this relationship to generate electricity on a large scale. It is at the heart of energy production in power plants, whether fossil fuel-powered, hydroelectric or renewable energy such as wind and solar.

C. Electrical transformers

Transformers are devices that allow you to adjust the AC voltage while conserving power. It is based on the laws of electromagnetism, especially on Faraday’s electromagnetic induction. By changing the number of turns of conductive wire in transformer windings, the output voltage can be adjusted without changing the current frequency. Transformers are crucial to the efficient distribution of electricity over long distances, helping to reduce energy loss during transmission.

What is the relationship between magnets and electricity?

In summary, electricity relies on charges to make magnets, while magnetism is used to generate electrical energy, thus creating a fundamental connection between these two phenomena. Likewise, magnetism can be harnessed to induce electrical currents, paving the way for large-scale electrical power generation. These interactions between electricity and magnetism support a range of technological innovations, from electric motors to smart grids.