In physics, electromagnetism is an interaction that occurs between particles with electric charge via electromagnetic fields. The electromagnetic force is one of the four fundamental forces of nature. It is the dominant force in the interactions of atoms and molecules. Electromagnetism can be thought of as a combination of electrostatics and magnetism, which are distinct but closely intertwined phenomena. Electromagnetic forces occur between any two charged particles. Electric forces cause an attraction between particles with opposite charges and repulsion between particles with the same charge, while magnetism is an interaction that occurs between charged particles in relative motion. These two forces are described in terms of electromagnetic fields. Macroscopic charged objects are described in terms of Coulomb's law for electricity and Ampère's force law for magnetism; the Lorentz force describes microscopic charged particles.
An electromagnetic field is a physical field, mathematical functions of position and time, representing the influences on and due to electric charges. The field at any point in space and time can be regarded as a combination of an electric field and a magnetic field. Because of the interrelationship between the fields, a disturbance in the electric field can create a disturbance in the magnetic field which in turn affects the electric field, leading to an oscillation that propagates through space, known as an electromagnetic wave.
Franz Anton Mesmer was a German physician with an interest in astronomy. He theorized the existence of a process of natural energy transference occurring between all animate and inanimate objects; this he called "animal magnetism", later referred to as mesmerism. Mesmer's theory attracted a wide following between about 1780 and 1850, and continued to have some influence until the end of the 19th century. In 1843, the Scottish doctor James Braid proposed the term "hypnotism" for a technique derived from animal magnetism; today the word "mesmerism" generally functions as a synonym of "hypnosis". Mesmer also supported the arts, specifically music; he was on friendly terms with Haydn and Mozart.
Magnetism is the class of physical attributes that occur through a magnetic field, which allows objects to attract or repel each other. Because both electric currents and magnetic moments of elementary particles give rise to a magnetic field, magnetism is one of two aspects of electromagnetism.
A magnetic field is a physical field that describes the magnetic influence on moving electric charges, electric currents, and magnetic materials. A moving charge in a magnetic field experiences a force perpendicular to its own velocity and to the magnetic field. A permanent magnet's magnetic field pulls on ferromagnetic materials such as iron, and attracts or repels other magnets. In addition, a nonuniform magnetic field exerts minuscule forces on "nonmagnetic" materials by three other magnetic effects: paramagnetism, diamagnetism, and antiferromagnetism, although these forces are usually so small they can only be detected by laboratory equipment. Magnetic fields surround magnetized materials, electric currents, and electric fields varying in time. Since both strength and direction of a magnetic field may vary with location, it is described mathematically by a function assigning a vector to each point of space, called a vector field.
A magnet is a material or object that produces a magnetic field. This magnetic field is invisible but is responsible for the most notable property of a magnet: a force that pulls on other ferromagnetic materials, such as iron, steel, nickel, cobalt, etc. and attracts or repels other magnets.
In physics and materials science, the Curie temperature (TC), or Curie point, is the temperature above which certain materials lose their permanent magnetic properties, which can (in most cases) be replaced by induced magnetism. The Curie temperature is named after Pierre Curie, who showed that magnetism is lost at a critical temperature.
A Treatise on Electricity and Magnetism is a two-volume treatise on electromagnetism written by James Clerk Maxwell in 1873. Maxwell was revising the Treatise for a second edition when he died in 1879. The revision was completed by William Davidson Niven for publication in 1881. A third edition was prepared by J. J. Thomson for publication in 1892.
Animal Magnetism is the seventh studio album by German rock band Scorpions, released in 1980. The RIAA certified the record as Gold on 8 March 1984, and Platinum on 28 October 1991.
Magnetism is a phenomenon in physics by which materials exert an attractive or repulsive force on other materials.
Biomagnetism is the phenomenon of magnetic fields produced by living organisms; it is a subset of bioelectromagnetism. In contrast, organisms' use of magnetism in navigation is magnetoception and the study of the magnetic fields' effects on organisms is magnetobiology.
Magnetic fluid may refer to:
In physics, Gauss's law for magnetism is one of the four Maxwell's equations that underlie classical electrodynamics. It states that the magnetic field B has divergence equal to zero, in other words, that it is a solenoidal vector field. It is equivalent to the statement that magnetic monopoles do not exist. Rather than "magnetic charges", the basic entity for magnetism is the magnetic dipole.
A spin model is a mathematical model used in physics primarily to explain magnetism. Spin models may either be classical or quantum mechanical in nature. Spin models have been studied in quantum field theory as examples of integrable models. Spin models are also used in quantum information theory and computability theory in theoretical computer science. The theory of spin models is a far reaching and unifying topic that cuts across many fields.
The term magnetic usually refers to magnetism.
Human magnetism is a popular name for the supposed ability of some humans to attract various objects to their skin. People alleged to have such an ability are often called human magnets. Although metal objects are the most prevalent material of attraction, some "human magnets" are also able to stick other types of materials to their skin, such as glass, porcelain, wood or plastic as well as metals with no ferromagnetic properties, such as brass and aluminium. However, none of the recorded claims of human magnetism corresponds with the physics of magnetism.
Animal magnetism, also known as mesmerism, is a theory invented by German doctor Franz Mesmer in the 18th century. It posits the existence of an invisible natural force (Lebensmagnetismus) possessed by all living things, including humans, animals, and vegetables. He claimed that the force could have physical effects, including healing.
The Royal Commission on Animal Magnetism involved two entirely separate and independent French Royal Commissions, each appointed by Louis XVI in 1784, that were conducted simultaneously by a committee composed of four physicians from the Paris Faculty of Medicine and five scientists from the Royal Academy of Sciences , and a second committee composed of five physicians from the Royal Society of Medicine .
