Most often called "voltage" (symbol E). It is the pressure applied to move electrons in a complete circuit. In a storage battery, EMF is the difference in potential between the positive and negative poles. Potential is limited by the number and type of cells and the strength of the electrolyte. EMF or voltage is measured by using a "voltmeter" connected in parallel tot he circuit being measured.
The electromotive force is the force that pushes electrons around a circuit. It can be supplied by a battery and is measured in units of volts. The electromotive force is often abbreviated to EMF. Rivers of Electrons
The potential difference between the two electrodes in a cell. The cell emf is the cell voltage measured when no current is flowing through the cell. It can be measured by means of a pH meter with high input impedance.
The work or energy which causes the flow of an electric current. Expressed as volts. It should be noted that the term "force" is a misnomer. However, the term is so well established that its use continues in spite of its being incorrect.
Electromotive force (emf) is defined as the amount of energy gained per unit charge that passes through a device in the opposite direction to the electric field existing across that device. It is measured in volts.