Search results
Results from the WOW.Com Content Network
Precision tests of QED have been performed in low-energy atomic physics experiments, high-energy collider experiments, and condensed matter systems. The value of α is obtained in each of these experiments by fitting an experimental measurement to a theoretical expression (including higher-order radiative corrections) that includes α as a parameter.
IEC EN 61000-4-9, Electromagnetic compatibility (EMC) - Part 4-9: Testing and measurement techniques - Pulse magnetic field immunity test; IEC EN 61000-4-11, Electromagnetic compatibility (EMC) - Part 4-11: Testing and measurement techniques - Voltage dips, short interruptions and voltage variations immunity tests; IEC EN 61000-4-13 ...
Electromagnetic testing (ET), as a form of nondestructive testing, is the process of inducing electric currents or magnetic fields or both inside a test object and observing the electromagnetic response. If the test is set up properly, a defect inside the test object creates a measurable response. The term "electromagnetic testing" is often ...
Eddy current testing (ECT) as a technique for testing finds its roots in electromagnetism. Eddy currents were first observed by François Arago in 1824, but French physicist Léon Foucault is credited with discovering them in 1855. ECT began largely as a result of the English scientist Michael Faraday's discovery of electromagnetic induction in
Electromagnetic compatibility (EMC) is the ability of electrical equipment and systems to function acceptably in their electromagnetic environment, by limiting the unintentional generation, propagation and reception of electromagnetic energy which may cause unwanted effects such as electromagnetic interference (EMI) or even physical damage to ...
Radiation resistance is the part of the resistance to current caused by power lost to radiation by an antenna. Unfortunately, it cannot be directly measured but is a component of the total resistance which includes the loss resistance. Loss resistance is the result of power lost to heat in the antenna materials, rather than to coherent radio ...
The resistance of a thin Permalloy film is shown here as a function of the angle of an applied external field. Thomson's experiments [4] are an example of AMR, [7] a property of a material in which a dependence of electrical resistance on the angle between the direction of electric current and direction of magnetization is observed.
An EMF meter is a scientific instrument for measuring electromagnetic fields (abbreviated as EMF). Most meters measure the electromagnetic radiation flux density (DC fields) or the change in an electromagnetic field over time (AC fields), essentially the same as a radio antenna, but with quite different detection characteristics.