Difference between revisions of "Electromagnetic wave"
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A transverse wave composed of an oscillating electrical field and a magnetic field that oscillate perpendicular to the electric field.<ref>Wile, Dr. Jay L. ''Exploring Creation With Physical Science''. Apologia Educational Ministries, Inc. 1999, 2000</ref> | A transverse wave composed of an oscillating electrical field and a magnetic field that oscillate perpendicular to the electric field.<ref>Wile, Dr. Jay L. ''Exploring Creation With Physical Science''. Apologia Educational Ministries, Inc. 1999, 2000</ref> | ||
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| + | The spectrum of electromagnetic waves has an extremely wide range from radio waves, micro waves, TeraHertz radiation, infrared (IR) radiation, visible light, ultraviolett (UV) light, far UV radiation, soft X-rays, hard X-rays and <math>\gamma</math>-radiation. | ||
Electromagnetic waves are well described by the classical laws of electricity and magnetism, known as Maxwell's equations: | Electromagnetic waves are well described by the classical laws of electricity and magnetism, known as Maxwell's equations: | ||
Revision as of 18:24, May 23, 2007
A transverse wave composed of an oscillating electrical field and a magnetic field that oscillate perpendicular to the electric field.[1]
The spectrum of electromagnetic waves has an extremely wide range from radio waves, micro waves, TeraHertz radiation, infrared (IR) radiation, visible light, ultraviolett (UV) light, far UV radiation, soft X-rays, hard X-rays and <math>\gamma</math>-radiation.
Electromagnetic waves are well described by the classical laws of electricity and magnetism, known as Maxwell's equations:
| Name | Partial Differential Equations | Integral Equations |
|---|---|---|
| Gauss's Law of Conservation: | <math>\nabla \cdot \mathbf{D} = \rho</math> | <math>\oint_S \mathbf{D} \cdot \mathrm{d}\mathbf{A} = \int_V \rho\, \mathrm{d}V</math> |
| Gauss' Law Of Magnetism: | <math>\nabla \cdot \mathbf{B} = 0</math> | <math>\oint_S \mathbf{B} \cdot \mathrm{d}\mathbf{A} = 0</math> |
| Faraday's Law of Induction: | <math>\nabla \times \mathbf{E} = -\frac{\partial \mathbf{B}} {\partial t}</math> | <math>\oint_C \mathbf{E} \cdot \mathrm{d}\mathbf{l} = - \int_S \frac{\partial\mathbf{B}}{\partial t} \cdot \mathrm{d} \mathbf{A}</math> |
| Ampère's Law of Circulation |
<math>\nabla \times \mathbf{H} = \mathbf{J} + \frac{\partial \mathbf{D}} {\partial t}</math> | <math>\oint_C \mathbf{H} \cdot \mathrm{d}\mathbf{l} = \int_S \mathbf{J} \cdot \mathrm{d} \mathbf{A} +
\int_S \frac{\partial\mathbf{D}}{\partial t} \cdot \mathrm{d} \mathbf{A}</math>
|
where B denotes the magnetic field, E denotes the electric field, H denotes the auxiliary magnetic field, J denotes the free current density, and <math>\rho</math> denotes the free electric charge density.
In the language of Exterior Calculus, Maxwell's equations can be rewritten much more compactly as:
- <math>\mathrm{d}\bold{F}=0</math>
- <math>\mathrm{d} * {\bold{F}}=\bold{J}</math>
where d is exterior derivative operator, * is the Hodge star operator, and F is the force exerted upon a charged particle by the electric field and magnetic field.
References
- ↑ Wile, Dr. Jay L. Exploring Creation With Physical Science. Apologia Educational Ministries, Inc. 1999, 2000