electromagnetism - Relation between Electric and magnetic fields - Physics Stack Exchange
In an electromagnetic wave,electric field and magnetic fields both have waveform i.e. magnitude of both can be expressed as function of (kx -wt) i.e f(kx - vt). There is a wonderful connection between c, the speed of light in a The energy of the wave is stored in the electric and magnetic fields. An electromagnetic field is a physical field produced by electrically charged .. Non-Ionizing Radiation, Part 1: Static and Extremely Biological Effects of Power Frequency Electric and Magnetic Fields (May ).Electromagnetic wave HD
Maxwell concluded that visible light was a small part of a vast spectrum of previously undiscovered types of electromagnetic radiation. Since Maxwell's time, virtually all of the non-visible parts of the electromagnetic spectrum have been observed.
Electromagnetic waves are of particular importance because they are our only source of information regarding the universe around us. Radio waves and microwaves which are comparatively hard to scatter have provided much of our knowledge about the centre of our own galaxy.
This is completely unobservable in visible light, which is strongly scattered by interstellar gas and dust lying in the galactic plane. For the same reason, the spiral arms of our galaxy can only be mapped out using radio waves.
Infrared radiation is useful for detecting proto-stars, which are not yet hot enough to emit visible radiation.
Electromagnetic field - Wikipedia
So Maxwell's equations imply that electro magnetic waves travel at the speed of light. But with respect to what frame of reference?
How can radiation be traveling one speed to a stationary observer on earth and the same speed relative to a spaceship traveling in its direction at half the speed of light? Since it always takes some amount of time for a a cause to manifest an effect, how can the time variation of a magnetic field instantly influence the electric field as Maxwell's Equations seem to imply?
This issue might best be approached through an analysis of electric and magnetic potentials. This Vector is the magnetic potential or the Vector Potential.
This Gauge Freedom allows us to assert that: Thus, the electromagnetic field may be viewed as a dynamic entity that causes other charges and currents to move, and which is also affected by them. These interactions are described by Maxwell's equations and the Lorentz force law. This discussion ignores the radiation reaction force. Feedback loop[ edit ] The behavior of the electromagnetic field can be divided into four different parts of a loop: A common misunderstanding is that a the quanta of the fields act in the same manner as b the charged particles that generate the fields.
In our everyday world, charged particles, such as electrons, move slowly through matter with a drift velocity of a fraction of a centimeter or inch per second, but fields propagate at the speed of light - approximately thousand kilometers or thousand miles a second.
The mundane speed difference between charged particles and field quanta is on the order of one to a million, more or less. Maxwell's equations relate a the presence and movement of charged particles with b the generation of fields.
Those fields can then affect the force on, and can then move other slowly moving charged particles. Charged particles can move at relativistic speeds nearing field propagation speeds, but, as Einstein showed[ citation needed ], this requires enormous field energies, which are not present in our everyday experiences with electricity, magnetism, matter, and time and space.