The full form of emf is electromotive force.
Electromotive Force Explained
Electromotive force (emf) is the electric potential generated either by an electrochemical cell or through a changing magnetic field. In simpler terms, it's the voltage developed by any source of electrical energy.
Here's a breakdown:
- Electrochemical Cell: This refers to batteries or other devices that convert chemical energy into electrical energy. The emf is the potential difference between the terminals of the cell when no current is flowing.
- Changing Magnetic Field: According to Faraday's Law of electromagnetic induction, a changing magnetic field induces an electric field, and therefore an electromotive force in any closed loop within the field. This is the principle behind generators.
Example
A common example is a battery. A 1.5V AA battery has an emf of 1.5 volts. This means that the battery can supply 1.5 Joules of energy for every Coulomb of charge that passes through a circuit connected to it.
Practical Insight
While often called a "force," electromotive force is technically a potential difference, measured in volts. It's the cause of current flow, not a force itself.
