what is an e.m.f
The term "e.m.f" stands for electromotive force. It represents the voltage or potential difference across a source such as a battery or generator when no current is flowing. The electromotive force is responsible for driving an electric current through a circuit.
To understand electromotive force, it's helpful to know some basic concepts in electricity. Voltage is the potential difference between two points in a circuit, which determines the flow of electric charges. A battery or generator acts as a source of voltage, supplying energy to the circuit.
To calculate the electromotive force, you typically need to know the difference in potential between the two points and the work done by the source per unit charge. In most cases, if you know the voltage across a source, it is the electromotive force.
To measure the electromotive force, you can use a voltmeter connected across the source terminals. It will provide you with the voltage reading, indicating the e.m.f.
Remember that electromotive force is different from electrical potential or voltage drop, which are the terms used to describe the voltage across components in a circuit as current flows through them.