- Tech know how online

electromotive force (EMF)

The electromotive force (EMF) is the voltage (U) that moves the electrons in a conductor.

The electromotive force differs from the voltage at the battery terminals or the battery voltage in that no current flows in the voltage source and therefore there is no voltage drop across the internal resistance.

Voltage source with internal and external resistance

Voltage source with internal and external resistance

The emf corresponds to the open circuit voltage or the open terminal voltage as long as no current flows across the internal resistance of the voltage source. In the case of batteries and accumulators, it can be measured with a high-impedance meter at the electrodes, and only if no electronic circuit or other load is connected.

Englisch: electromotive force - EMF
Updated at: 03.12.2013
#Words: 112
Links: enhanced metafile (WMF) (EMF), voltage, conductor, battery, current
Translations: DE

All rights reserved DATACOM Buchverlag GmbH © 2024