Difference Between Voltage and EMF


What is Voltage?

The required amount of energy to move the unit charge from one point to another is known as Voltage. In other words, voltage is defined as the difference between electric potentials. It is represented by the symbol of capital “V” and measured in Volts denoted by “V” and measured by a voltmeter.

What is EMF?

EMF or Electromotive Force is the energy supply to the charge by a battery cell. In other words, EMF produces and maintains voltage inside an active cell and supplies energy in joules to each unit of coulomb charge. It is represented by “ε” and the measuring unit is same as voltage i.e. Volt.

Difference Between Voltage and EMF



It is the difference potential difference between two points

It denotes the voltage produced inside the electric source.

V = IR


V = Voltage in Volts

I = Current in Amperes

R = Resistance in Ohms

E = I(R + r)

E = W/Q


E or ε = EMF in Volts

W = Work done energy in Joules

Q = Charge in Coulombs

r = Internal resistance of the battery cell in ohms

Measure between any two points.

Measure between the end point of the source, when no current flows through it.

Voltage follows a non-coulomb force operation.

Electromotive force follows the coulomb force operation.

It is measured with a voltmeter

It measured with EMF meter

Its intensity is not constant

Its intensity is constant

Work performed in moving a charge from one point to another through a conductor wire.

In a source, external forces work performed in moving a charge from one point to another.

Voltage depends on the circuit resistance

EMF doesn’t depends on the circuit resistance.

Electric and magnetic field

Dynamo, electrochemical cell, transformer, solar cell, photodiodes etc.

Voltage is denoted by the letter V.

Electromotive force is denoted by .


READ HERE  What is difference between MCB and RCCB?


Please enter your comment!
Please enter your name here