Electromagnetic field - Incompressible fluids. The electric and magnetic vector fields can be thought of as being the velocities of a pair of incompressible fluids which permeate space. In the absence of charges these fluids would be at rest, so that their velocity fields would be zero. Since both fluids are incompressible, their densities do not change: it is not possible to compress magnetic or electric fluid into a smaller space. ...

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Electromagnetic field, Electromagnetic field - Behavior of the electromagnetic fields, Electromagnetic field - Incompressible fluids, Electromagnetic field - Source and Sinks, Electromagnetic field - The two fluids, Electromagnetic field - The vortex, Electromagnetic field - Summary, Electromagnetic field - Negative Feedback Loop, Electromagnetic field - Positive Feedback Loop, Electromagnetic field - Flaw in the velocity field interpretation, Electromagnetic field - The field as a stream of moving photons, Electromagnetic field - Light and electromagnetic waves, Electromagnetic field - The electromagnetic field as a feedback loop

Read more here: » Electromagnetic field: Encyclopedia II - Electromagnetic field - Behavior of the electromagnetic fields

See also:

Electromagnetic field, Electromagnetic field - Behavior of the electromagnetic fields, Electromagnetic field - Incompressible fluids, Electromagnetic field - Source and Sinks, Electromagnetic field - The two fluids, Electromagnetic field - The vortex, Electromagnetic field - Summary, Electromagnetic field - Negative Feedback Loop, Electromagnetic field - Positive Feedback Loop, Electromagnetic field - Flaw in the velocity field interpretation, Electromagnetic field - The field as a stream of moving photons, Electromagnetic field - Light and electromagnetic waves, Electromagnetic field - The electromagnetic field as a feedback loop

Read more here: » Electromagnetic field: Encyclopedia II - Electromagnetic field - The electromagnetic field as a feedback loop

Electrically charged particles are constantly emitting (or absorbing) photonic fluid, which is more commonly known as light. So how is light related to electromagnetic waves? Electromagnetic (E-M) waves are the undulatory movements of light, which can always be observed to be emitted by electric charges undergoing acceleration. If a charged particle is at rest, then it does not emit electromagnetic waves. Instead, it is surrounded by an electrostatic field. If a charged particle is in inertial motion, then the electrostatic field is j ...

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Electromagnetic field, Electromagnetic field - Behavior of the electromagnetic fields, Electromagnetic field - Incompressible fluids, Electromagnetic field - Source and Sinks, Electromagnetic field - The two fluids, Electromagnetic field - The vortex, Electromagnetic field - Summary, Electromagnetic field - Negative Feedback Loop, Electromagnetic field - Positive Feedback Loop, Electromagnetic field - Flaw in the velocity field interpretation, Electromagnetic field - The field as a stream of moving photons, Electromagnetic field - Light and electromagnetic waves, Electromagnetic field - The electromagnetic field as a feedback loop

Read more here: » Electromagnetic field: Encyclopedia II - Electromagnetic field - Light and electromagnetic waves

Classical electrodynamics (or classical electromagnetism) is a theory of electromagnetism that was developed over the course of the 19th century, most prominently by James Clerk Maxwell. It provides an excellent description of electromagnetic phenomena whenever the relevant length scales and field strengths are large enough that quantum mechanical effects are negligible (see quantum electrodynamics). Classical electromagnetism - Lorentz force. The electromagnetic field exerts the following force (oft ...

Including:

• Classical electromagnetism - Lorentz force
• Classical electromagnetism - The Electric Field E
• Classical electromagnetism - Electromagnetic waves
• Classical electromagnetism - General Field Equations
• Classical electromagnetism - Also See

Read more here: » Classical electromagnetism: Encyclopedia - Classical electromagnetism

A magnet is an object that has a magnetic field. The word magnet comes from the Greek "magnítis líthos" (μαγνήτης λίθος), which means "magnesian stone". Magnesia is an area in Greece (Now Manisa, Turkey) where deposits of magnetite have been discovered since antiquity. Magnet - Introduction. In the modern sense, a magnet is any material that has a magnetic field. It can be in the form of a permanent magnet or an electromagnet. Permanent magnets do not rely upon outside in ...

Including:

• Magnet - Introduction
• Magnet - Physical origin of magnetism
• Magnet - Permanent Magnets
• Magnet - Electromagnets
• Magnet - Characteristics of magnetic materials
• Magnet - Permanent magnets and dipoles
• Magnet - North/south pole designation and the Earth's magnetic field
• Magnet - Common uses for magnets
• Magnet - How to magnetize materials
• Magnet - How to demagnetize materials
• Magnet - Types of permanent magnets
• Magnet - Magnetic forces
• Magnet - Magnets and other magnets
• Magnet - Magnets and ferromagnetic materials
• Magnet - Magnets and diamagnetic materials
• Magnet - Magnets and paramagnetic materials
• Magnet - Calculating the magnetic force
• Magnet - Online references
• Magnet - Printed references
• Magnet - External articles

Read more here: » Magnet: Encyclopedia - Magnet

Electricity is a property of matter that results from the presence of electric charge. Together with magnetism, it constitutes the fundamental interaction known as electromagnetism. Electricity is responsible for many well-known physical phenomena such as lightning, electric fields and electric currents, and is put to use in industrial applications such as electronics and electric power. Electricity - Concepts in electricity. In casual usage, the term electricity is applied to several related concept ...

Including:

• Electricity - Concepts in electricity
• Electricity - History
• Electricity - Ancient
• Electricity - Modern
• Electricity - Electric charge
• Electricity - Electric field
• Electricity - Electric potential
• Electricity - Electric current
• Electricity - Electrical energy
• Electricity - Electric power
• Electricity - SI electricity units
• Electricity - Devices
• Electricity - Engineering
• Electricity - Safety
• Electricity - Electrical phenomena in nature

Read more here: » Electricity: Encyclopedia - Electricity

In physics, a magnetic field is an entity produced by moving electric charges (electric currents) that exerts a force on other moving charges. (The quantum-mechanical spin of a particle produces magnetic fields and is acted on by them as though it were a current; this accounts for the fields produced by "permanent" ferromagnets.) A magnetic field is a vector field: it associates with every point in space a (pseudo-)vector that may vary in time. The direction of the field is the equilibrium direction of a compass needle placed in the f ...

Including:

• Magnetic field - Symbols and terminology
• Magnetic field - Definition
• Magnetic field - Current loop
• Magnetic field - Point charge generating magnetic field
• Magnetic field - Vector calculus
• Magnetic field - Energy in the magnetic field
• Magnetic field - Properties
• Magnetic field - Magnetic field lines
• Magnetic field - Pole labeling confusions
• Magnetic field - Rotating magnetic fields
• Magnetic field - External articles

Read more here: » Magnetic field: Encyclopedia - Magnetic field

It is often convenient to understand the electromagnetic field in terms of two separate fields: the electric field and the magnetic field. A non-zero electric field is produced by the presence of electrically charged particles, and gives rise to the electric force; this is the force that causes static electricity and drives the flow of electric charge (electric current) in electrical conductors. The magnetic field, on the other hand, can be produced by the motion of electric charges, or electric curre ...

See also:

Electromagnetism, Electromagnetism - Electric and magnetic fields, Electromagnetism - The electromagnetic force, Electromagnetism - Origins of electromagnetic theory, Electromagnetism - Failures of classical electromagnetism, Electromagnetism - SI electricity units

Read more here: » Electromagnetism: Encyclopedia II - Electromagnetism - Electric and magnetic fields

Alternative interpretation would be that the field is not actually a velocity field, but a flux density field of photonic fluid, which is constantly moving at the same speed: the speed of light, independent of the speed of the observer (the charged object). Photonic fluid never changes speed but can change net direction and the intensity of its net movement in that direction. The velocity field interpretation is related to the hypothesis of a luminiferous aether through which electromagnetic waves would propagate. The proposition that ...

See also:

Electromagnetic field, Electromagnetic field - Behavior of the electromagnetic fields, Electromagnetic field - Incompressible fluids, Electromagnetic field - Source and Sinks, Electromagnetic field - The two fluids, Electromagnetic field - The vortex, Electromagnetic field - Summary, Electromagnetic field - Negative Feedback Loop, Electromagnetic field - Positive Feedback Loop, Electromagnetic field - Flaw in the velocity field interpretation, Electromagnetic field - The field as a stream of moving photons, Electromagnetic field - Light and electromagnetic waves, Electromagnetic field - The electromagnetic field as a feedback loop

Read more here: » Electromagnetic field: Encyclopedia II - Electromagnetic field - The field as a stream of moving photons

The fluid analogy is flawed, in that objects immersed in a moving fluid (e.g. a river) tend to be pushed by that fluid in such a way that the velocity of the object aligns with the velocity of the fluid. Once the velocities are aligned, the fluid's motion should vanish from the object's point of view. However, the force of an electric field on a charged particle is , a force that is independent of the velocity of the particle. This means that the particle will accelerate continually in the direction of the field. If the field were the ...

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Electromagnetic field, Electromagnetic field - Behavior of the electromagnetic fields, Electromagnetic field - Incompressible fluids, Electromagnetic field - Source and Sinks, Electromagnetic field - The two fluids, Electromagnetic field - The vortex, Electromagnetic field - Summary, Electromagnetic field - Negative Feedback Loop, Electromagnetic field - Positive Feedback Loop, Electromagnetic field - Flaw in the velocity field interpretation, Electromagnetic field - The field as a stream of moving photons, Electromagnetic field - Light and electromagnetic waves, Electromagnetic field - The electromagnetic field as a feedback loop

Read more here: » Electromagnetic field: Encyclopedia II - Electromagnetic field - Flaw in the velocity field interpretation

The algebraic classification of bivectors given above has an important application in relativistic physics: the electromagnetic field is represented by a skew-symmetric second rank tensor (the electromagnetic field tensor) so we immediately obtain an algebraic classification of electromagnetic fields. Recall that for in a cartesian chart on Minkowski spacetime, the electromagnetic field tensor has components where Ex,Ey,E ...

See also:

Classification of electromagnetic fields, Classification of electromagnetic fields - The classification theorem, Classification of electromagnetic fields - Physical interpretation, Classification of electromagnetic fields - Invariants, Classification of electromagnetic fields - Curved Lorentzian manifolds

Read more here: » Classification of electromagnetic fields: Encyclopedia II - Classification of electromagnetic fields - Physical interpretation

Hidden beneath the surface of this overly complex mathematical equation is an ingenious unification of maxwell's equations for electromagnetism. Consider the electrostatic equation which tells us that the divergence of the Electric field vector is equal to the charge density, and the electrodynamic equation that is the change of the electric field with respect to time, minus the curl of the magnetic field vector, is equal to negative four pi times the current density ...

See also:

Electromagnetic tensor, Electromagnetic tensor - Details, Electromagnetic tensor - Derivation, Electromagnetic tensor - Significance of the Field Tensor, Electromagnetic tensor - The field tensor and relativity, Electromagnetic tensor - Role in Quantum Electrodynamics and Field Theory

Read more here: » Electromagnetic tensor: Encyclopedia II - Electromagnetic tensor - Significance of the Field Tensor

As simple and satisfying as Coulomb's equation may be, it is not entirely correct in the context of classical electromagnetism. Problems arise because changes in charge distributions require a non zero amount of time to be "felt" elsewhere (required by special relativity). For the fields of general charge distributions, the retarded potentials can be computed and differentiated accordingly to yield Jefimenko's Equations. Retarded potentials can also be derived for point charges, and the equations are known as the Liénard-Wiech ...

See also:

Classical electromagnetism, Classical electromagnetism - Lorentz force, Classical electromagnetism - The Electric Field E, Classical electromagnetism - Electromagnetic waves, Classical electromagnetism - General Field Equations, Classical electromagnetism - Also See

Read more here: » Classical electromagnetism: Encyclopedia II - Classical electromagnetism - General Field Equations

Hidden beneath the surface of this overly complex mathematical equation is an ingenious unification of maxwell's equations for electromagnetism. Consider the electrostatic equation which tells us that the divergence of the Electric field vector is equal to the charge density, and the electrodynamic equation that is the change of the electric field with respect to time, minus the curl of the magnetic field vector, is equal to negative four pi times the current density. These two equations for electricity reduce ...

See also:

Electromagnetic tensor, Electromagnetic tensor - Details, Electromagnetic tensor - Derivation, Electromagnetic tensor - Significance of the Field Tensor, Electromagnetic tensor - The field tensor and relativity, Electromagnetic tensor - Role in Quantum Electrodynamics and Field Theory

Read more here: » Electromagnetic tensor: Encyclopedia II - Electromagnetic tensor - Significance of the Field Tensor

The electric field E is defined such that, on a stationary charge: where q0 is what is known as a test charge. The size of the charge doesn't really matter, as long as it is small enough as to not influence the electric field by its mere presence. What is plain from this definition, though, is that the unit of E is N/C, or newtons per coulomb. This unit is equal to V/m (volts per meter), see below. The above definition seems a little bit circular but, in electrostatics, where charges are not moving, Coulom ...

See also:

Classical electromagnetism, Classical electromagnetism - Lorentz force, Classical electromagnetism - The Electric Field E, Classical electromagnetism - Electromagnetic waves, Classical electromagnetism - General Field Equations, Classical electromagnetism - Also See

Read more here: » Classical electromagnetism: Encyclopedia II - Classical electromagnetism - The Electric Field E

The field tensor derives its name from the fact that the electromagnetic field is found to obey the tensor transformation law, this general property of (non-gravitational) physical laws being recognised after the advent special relativity. This theory stipulated that all the (non-gravitational) laws of physics should take the same form in all coordinate systems - this led to the introduction of tensors. The tensor formalism also leads to a mathematically elegant presentation of physical laws. For example, Maxwell's equations ...

See also:

Electromagnetic tensor, Electromagnetic tensor - Details, Electromagnetic tensor - Derivation, Electromagnetic tensor - Significance of the Field Tensor, Electromagnetic tensor - The field tensor and relativity, Electromagnetic tensor - Role in Quantum Electrodynamics and Field Theory

Read more here: » Electromagnetic tensor: Encyclopedia II - Electromagnetic tensor - The field tensor and relativity

A (real) bivector field may be viewed, at any given event in a spacetime, as a skew-symmetric linear operator on a four-dimensional (real) vector space, . Here, the vector space is the tangent space at the given event, and thus isomorphic as a (real) inner product space to E1,3. That is, it has the same notion of vector magnitude and angle (or inner product) as Minkowski spacetime. In the remainder of this section (and in the next section), we'll assume our spacetime is Minkowski spacetime. This simplifies the ...

See also:

Classification of electromagnetic fields, Classification of electromagnetic fields - The classification theorem, Classification of electromagnetic fields - Physical interpretation, Classification of electromagnetic fields - Invariants, Classification of electromagnetic fields - Curved Lorentzian manifolds

Read more here: » Classification of electromagnetic fields: Encyclopedia II - Classification of electromagnetic fields - The classification theorem

The Lagrangian of QED extends beyond the classical Lagrangian established in relativity from to incorporate the creation and annhilation of photons (and electrons). In Quantum field theory, it is used for the template of the gauge field strength tensor. That is used in addition to the local interaction Lagrangian, nearly identical to its role in QED. ...

See also:

Electromagnetic tensor, Electromagnetic tensor - Details, Electromagnetic tensor - Derivation, Electromagnetic tensor - Significance of the Field Tensor, Electromagnetic tensor - The field tensor and relativity, Electromagnetic tensor - Role in Quantum Electrodynamics and Field Theory

Read more here: » Electromagnetic tensor: Encyclopedia II - Electromagnetic tensor - Role in Quantum Electrodynamics and Field Theory

Electric charges act either as sources or sinks of the electric fluid. An electron is constantly absorbing electric fluid around it at some rate, call it ε. Protons are the reverse: they constantly pour electric "fluid" towards the surrounding space at rate ε, so fluid moves away from the proton with speed (where r is distance of the fluid away from the proton) so that the total flux of fluid going through any (imaginary) sphere which contains that proton is the area of the sphere times the speed of the fluid flowing through it: .

Electromagnetic field, Electromagnetic field - Behavior of the electromagnetic fields, Electromagnetic field - Incompressible fluids, Electromagnetic field - Source and Sinks, Electromagnetic field - The two fluids, Electromagnetic field - The vortex, Electromagnetic field - Summary, Electromagnetic field - Negative Feedback Loop, Electromagnetic field - Positive Feedback Loop, Electromagnetic field - Flaw in the velocity field interpretation, Electromagnetic field - The field as a stream of moving photons, Electromagnetic field - Light and electromagnetic waves, Electromagnetic field - The electromagnetic field as a feedback loop

Read more here: » Electromagnetic field: Encyclopedia II - Electromagnetic field - Source and Sinks

In the original paper, because compact notations based on vectors had not yet been introduced, Maxwell formulated the equations in terms of 20 equations in 20 unknowns, as described in the Maxwell's equations article. Maxwell also included several equations now considered auxiliary to the core of Maxwell's equations. In modernized notation, the equations originally listed by Maxwell were: See also:

A Dynamical Theory of the Electromagnetic Field, A Dynamical Theory of the Electromagnetic Field - The original equations, A Dynamical Theory of the Electromagnetic Field - Quotes

Read more here: » A Dynamical Theory of the Electromagnetic Field: Encyclopedia II - A Dynamical Theory of the Electromagnetic Field - The original equations