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electromagnet. A magnet made by wrapping a coil of wire around an iron bar and passing an electric current through the coil. The iron core increases the solenoid’s magnetic field strength....
An electromagnet can be defined as a magnet which functions on electricity. Unlike a permanent magnet, the strength of an electromagnet can be changed by changing the amount of electric current that flows through it. If the current flow is cut, the property of magnetism ceases to exist.
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- A magnet that consists of a piece of iron or steel surrounded by a coil is known as an electromagnet. The metal becomes magnetic when an electric c...
- A magnet has three properties and that are attractive prosperity, repulsive property and directive property.
- An object which is capable of producing magnetic fields and attracting unlike poles and repelling like poles.
- Permanent magnets find applications in generators, electric accelerators, and electric motors.
- Electromagnets can store huge amounts of energy in their magnetic field. If the electric current is interrupted, the energy will discharge. Also, t...
Electromagnetism is a branch of physics that deals with the study of the electromagnetic force. Learn the principles of electromagnetism and electromagnetic induction with examples, formula and definition.
- 96 min
- Electromagnetism is a branch of physics that involves the study of electromagnetic force. It is a type of interaction that occurs between electrica...
- The electromagnetic force is a force that acts between charged particles and is a combination of electrical and magnetic forces.
- Faraday’s Law states that whenever there is relative motion between magnetic field and conductor, the flux linkage changes and this change in flux...
- Electromagnetic induction is the production of an electromotive force across an electrical conductor in a changing magnetic field.
- Electromagnetic waves are propagated by oscillating electric and magnetic waves at right angles to each other.
Jul 18, 2024 · Electromagnetism Examples. Compasses: A compass needle aligns with the Earth’s magnetic field, pointing north-south. Electric Bells: When activated, an electromagnet pulls a metal arm to strike a bell. Speakers: Electromagnets vibrate a flexible cone to produce sound from electrical signals.
- Overview
- Fundamentals
electromagnetism, science of charge and of the forces and fields associated with charge. Electricity and magnetism are two aspects of electromagnetism.
Electricity and magnetism were long thought to be separate forces. It was not until the 19th century that they were finally treated as interrelated phenomena. In 1905 Albert Einstein’s special theory of relativity established beyond a doubt that both are aspects of one common phenomenon. At a practical level, however, electric and magnetic forces behave quite differently and are described by different equations. Electric forces are produced by electric charges either at rest or in motion. Magnetic forces, on the other hand, are produced only by moving charges and act solely on charges in motion.
Electric phenomena occur even in neutral matter because the forces act on the individual charged constituents. The electric force in particular is responsible for most of the physical and chemical properties of atoms and molecules. It is enormously strong compared with gravity. For example, the absence of only one electron out of every billion molecules in two 70-kilogram (154-pound) persons standing two metres (two yards) apart would repel them with a 30,000-ton force. On a more familiar scale, electric phenomena are responsible for the lightning and thunder accompanying certain storms.
Electric and magnetic forces can be detected in regions called electric and magnetic fields. These fields are fundamental in nature and can exist in space far from the charge or current that generated them. Remarkably, electric fields can produce magnetic fields and vice versa, independent of any external charge. A changing magnetic field produces an electric field, as the English physicist Michael Faraday discovered in work that forms the basis of electric power generation. Conversely, a changing electric field produces a magnetic field, as the Scottish physicist James Clerk Maxwell deduced. The mathematical equations formulated by Maxwell incorporated light and wave phenomena into electromagnetism. He showed that electric and magnetic fields travel together through space as waves of electromagnetic radiation, with the changing fields mutually sustaining each other. Examples of electromagnetic waves traveling through space independent of matter are radio and television waves, microwaves, infrared rays, visible light, ultraviolet light, X-rays, and gamma rays. All of these waves travel at the same speed—namely, the velocity of light (roughly 300,000 kilometres, or 186,000 miles, per second). They differ from each other only in the frequency at which their electric and magnetic fields oscillate.
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Everyday modern life is pervaded by electromagnetic phenomena. When a lightbulb is switched on, a current flows through a thin filament in the bulb, and the current heats the filament to such a high temperature that it glows, illuminating its surroundings. Electric clocks and connections link simple devices of this kind into complex systems such as...
Sep 6, 2024 · Electromagnet, device consisting of a core of magnetic material surrounded by a coil through which an electric current is passed to magnetize the core. An electromagnet is used wherever controllable magnets are required, as in contrivances in which the magnetic flux is to be varied, reversed, or.
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Jul 18, 2023 · What do a wrecking yard, a rock concert and your front door have in common? They each use electromagnets, devices that create a magnetic field through the application of electricity. Wrecking yards employ extremely powerful electromagnets to move heavy pieces of scrap metal or even entire cars from one place to another.
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