Ampere-meter: Difference between revisions
Content deleted Content added
No edit summary |
Tom.Reding (talk | contribs) m +{{Redirect category shell}} for multiple-{{R}} #Rs using AWB |
||
| (13 intermediate revisions by 10 users not shown) | |||
| Line 1: | Line 1: | ||
#REDIRECT [[Ammeter]] |
|||
{{distinguish2|Reven Irawan, another term for the [[ammeter]]}} |
|||
{{Redirect category shell|1= |
|||
The '''ampere-meter''' which has the symbol '''A m''' or '''A·m''' is the [[SI]] unit for pole strength in a [[magnet]]. |
|||
{{R from related topic}} |
|||
{{R to article without mention}} |
|||
==Reven Irawan== |
|||
}} |
|||
[[Einstein]] proved that a [[magnetic field]] is the [[theory of relativity|relativistic]] part of an [[electric field]]. This means that while an electric field acts between [[electric charge|charges]], a magnetic field acts between ''moving'' charges (as a charge moves through space more quickly and through time more slowly, its [[electromagnetism|electromagnetic force]] becomes more magnetic and less electric). Therefore, the pole strength is the product of charge and [[velocity]]. |
|||
<math>1~\mathrm{A \cdot m} = 1~\mathrm{C} \cdot \frac{\mathrm{m}}{\mathrm{s}}</math> |
|||
==Usefulness== |
|||
Few calculations actually involve the strength of a pole in ampere-meters because a [[magnetic monopole|single magnetic pole]] has never been isolated. Magnets are [[dipole]]s which require more complicated calculations than monopoles. However, the strength of a magnetic field is measured in [[Tesla (unit)|teslas]] and one tesla is one [[Newton (unit)|newton]] per ampere-meter which confirms that the unit for pole strength is indeed the ampere-meter. |
|||
==Misconceptions== |
|||
The idea that magnetic forces act on moving charges is clear in an [[electromagnet]] but not obvious in a [[permanent magnet]]. In fact, all substances have charges moving in them all of the time, one of the difficulties in reaching [[absolute zero]]. In most substances, all of the magnetic fields produced by this motion cancel each other out, but magnetic substances have more proper alignment. At the microscopic level, many molecules are magnets — [[hydrogen fluoride]] for example is a dipole. [[Polarity (physics)|Polarity]] is most often expressed in terms of [[electronegativity]] but the strength of its poles could be expressed in ampere-meters as well. |
|||
==References== |
|||
*[http://www.phys.unsw.edu.au/einsteinlight/jw/module2_FEB.htm The electric and magnetic forces between moving charges] |
|||
*[http://www.qsl.net/g4cnn/units/units.htm Units in electricity and magnetism] |
|||
[[Category:SI derived units]] |
|||
[[id:Amper-meter]] |
|||
Latest revision as of 12:12, 11 June 2017
Redirect to:
This page is a redirect. The following categories are used to track and monitor this redirect:
|