The AMPERE association and trends in its biennial conferences

A C Metaxas1

  • 1EUG, Engineering Dept., University of Cambridge, England UK CB2 1PZ.

Related Concept Videos

Electrical Current01:10

Electrical Current

Electrical current is defined as the rate at which charge flows. When there is a large current present, such as that used to run a refrigerator, a large amount of charge moves through the wire in a small amount of time. If the current is small, such as that used to operate a handheld calculator, a small amount of charge moves through the circuit over a long period of time. The SI unit for current is the ampere (A), named for the French physicist André-Marie Ampère (1775–1836). An ampere is the...
Ampere's Law01:18

Ampere's Law

A fundamental property of a static magnetic field is that it is not conservative, unlike an electrostatic field. Instead, there is a relationship between the magnetic field and its source, electric current. Mathematically, this is expressed in terms of the line integral of the magnetic field, which is also known as Ampère’s law. It is valid only if the currents are steady and no magnetic materials or time-varying electric fields are present.
Ampère's law states that for any closed looped path,...
Ampere's Law: Problem-Solving01:31

Ampere's Law: Problem-Solving

Ampere's law states that for any closed looped path, the line integral of the magnetic field along the path equals the vacuum permeability times the current enclosed in the loop. If the fingers of the right hand curl along the direction of the integration path, the current in the direction of the thumb is considered positive. The current opposite to the thumb direction is considered negative.
Specific steps need to be considered while calculating the symmetric magnetic field distribution using...
Displacement Current01:19

Displacement Current

Ampère's law, in its usual form, does not work in places where the current changes with time and is not steady. Thus, Maxwell suggested including an additional contribution, called the displacement current, Id, to the real conduction current I.
Ampere's Law in Matter01:22

Ampere's Law in Matter

The total current density in magnetized material is the sum of the free and bound current densities. The free current arises due to the motion of free electrons within the material, while the bound current arises due to the alignment of magnetic dipole moments.
The differential form of Ampere's law in vacuum states that the curl of the magnetic field equals the permeability times the current density. In a magnetized material, the law is modified to incorporate the free and bound current...
Ampere-Maxwell's Law: Problem-Solving01:17

Ampere-Maxwell's Law: Problem-Solving

A parallel-plate capacitor with capacitance C, whose plates have area A and separation distance d, is connected to a resistor R and a battery of voltage V. The current starts to flow at t = 0. What is the displacement current between the capacitor plates at time t? From the properties of the capacitor, what is the corresponding real current?
To solve the problem, we can use the equations from the analysis of an RC circuit and Maxwell's version of Ampère's law.
For the first part of the problem,...