EMF Full Form

EMF full form is Electromotive Force which refers to the transferring of energy to a circuit per unit of electric charge, it is measured in volts. EMF is prevalent in devices that convert into chemical energy such as batteries. Basically, to operate a battery, one terminal turns negatively charged while the other becomes positively charged, so electromotive force can be called work done on a unit electric charge. The energy conversion process is conducted through physical force applied on electric charges. 

What is EMF Full Form?

EMF stands for electromotive force and is a charge pump that helps in pushing positive charges from a low-pressure area to a high-pressure area via chemical or mechanical means. Devices like electric generators, transformers, electrochemical cells, solar cells, photodiodes and inductors. Electromotive force is only generated in situations when magnetic field fluctuation happens on a surface.

Devices modeled on two-terminal systems the EMF can generate an electric current in case an external circuit is connected to the terminals. Well, emf is responsible for giving rise to voltage but some differences lie between this force and voltage. To gain a better insight into the concept of electromotive force, go through our article. 

Overview of EMF

Measurements and Important Specifications of EMF

As mentioned above EMF full form is electromotive force. It is represented by the symbol ε. A formula is used for calculating or defining electromotive force.

 ε= V+Ir

In this formula

• V stands for voltage in a cell
• R is the initial resistance of a cell
• I represent the current flowing across the circuit
•  Ε is the electromotive force

EMF is measured in terms of a volt. If we try representing the force through numerical, then it can be defined as the number of joules of energy offered by a source dividend by each coulomb that enables an electric charge worth one unit.

Volts= Joules/Coulombs

If we take the instance of a battery’s operation, we will find there's an occurrence of charge separation between positive (P) and negative(N) terminal and it results in an electrostatic field, Eopen circuit that points from P to N, when connected to a circuit emf in the source will be able to drive current from N to P. 

A Brief History of Electromotive Force (EMF Full Form)

Alessandro Volta, an Italian physicist coined the term force motrice electrique for defining the active agent present in a battery, later it began to be called electromotive force. In 1830, Michael Faraday the English scientist who offered great insight into electromagnetism and electrochemistry, confounded the theory of chemical reactions on electrode-electrolyte interfaces. 

As per his theory, chemical reactions that occur in two interfaces offer seats of EMF for the voltaic cell. This theory claims that the electromotive force cannot be called an endless energy source instead they just drive the current.

Is Potential Difference Related to EMF?

Many confuse electromotive force with the electrical potential difference (voltage) however, they are two distinct concepts. Though EMF results from potential differences, potential difference is not actually the cause of electromotive force. To gain a deeper understanding of the EMF and potential differences, go through the below-mentioned examples.

• Like a battery, solar cells and photodiodes are regarded as an EMF source that generates electrical voltage through charge separation powered by light and not by chemical reaction.
• In a circuit, electrical potential does not alone account for the total electromotive force as in the case of a resistor connected with a voltaic cell. 
• In a circuit connected to an electric generator that drives current through a resistor, the EMF arises from the generator’s time-varying magnetic field that ultimately creates electrical potential. 

It can be said that the potential difference is different from the induced electromagnetic field. When the current moves from A to B point potential difference remains unaffected. Remember, the electromotive force cannot be measured directly with the help of potential difference at the time of charging of a cell as voltage remains dissipated inside a source. 

How Faraday’s Law of Induction Relates to EMF?

Faraday’s law of induction forms the basis of the principle behind the working of electric motors, generators, transformers and inductors. This law predicts the way an electromagnetic field will interact with a circuit producing electromotive force; this phenomenon is termed electromagnetic induction. 

Faraday’s law claims that EMF exists on a conductive loop when variation in time takes place in a magnetic flux while covering a surface enclosed by a loop. An important aspect of the law has been used to refute another popular theory which is called the Maxwell-Faraday equation. In the Maxwell-Faraday equation, the equation definition is only transformer emf whereas Faraday’s law is concerned with motional as well as transformer emf.