Difference Between Voltage And Current

What is Current?

In electric circuits, current is the flow of electric charge. It’s really electrons (charged particles) that move around in circuits. Electric current are the electrons or negatively charged particles that move around in circuits. So when current flows in some direction in a circuit, the actual physical effect is electrons flowing in the opposite direction.

The SI unit of current is ampere which is denoted by “A”. If one coulomb charge passes through a conducting point in one second, the amount of current is known as one ampere. A 1 Ampere (1A) of current is the 6.24×1018 electrons charge carrier.

There are mainly two types of currents i.e. AC and DC (Alternating Current & Direct Current).

  1. AC Current: An AC (Alternating Current) changes its direction and magnitude continuously throughout the time.
  2. DC Current: A DC (Direct Current) has the constant magnitude which doesn’t change its polarity or direction throughout the time.

The electronic current flow is from negative to positive due to vast amount of negative charge carriers (electronic engineering) while in the conventional current flows from positive to negative (electrical engineering). It is only assumed for current direction flow while solving and analyzing electric circuit although the amount of current is same in both cases.

What is Voltage?

Voltage is the electromotive force, which is responsible for the movement of electrons or electric current through a circuit. The electrical potential difference between two points is the voltage between those two points. The overhead transmission lines that possess very high voltage used to transmit power over long distance to load center (cities, homes & industries).

Voltage is the effect of electromotive force (EMF) and represented by the symbol of V. The SI unit of voltage is “volt” which is also denoted by the symbol of “V”. A Volt is the potential difference which moves one joule of energy per coulomb charge between two points. One volt is the difference of electric positional equal to one ampere of current dissipates one watt of power between two conducting points.

There are two basic types of voltages i.e. Alternating Voltage and Direct Voltage

  1. Alternating Voltage: An AC voltage changes its direction and magnitude continuously throughout the time. Alternating voltages can be generated by alternators.
  2. Direct Voltage: DC Voltage has the constant magnitude which doesn’t change its polarity throughout the time. Direct voltage can be generated by electrochemical cells and batteries.

Also Read: Difference Between Volts And Amps

Voltage vs Current In Tabular Form

DescriptionVoltage is the potential difference between two points in an electric field, which causes current to flow in the circuit.Current is the rate of flow of electrons is called current.
SymbolVoltage is represented by “V”Current is represented by “I”
UnitVolt “V”Ampere “A”
Unit Charge1 Joule / Coulomb = 1 Volt1 Coulomb / Second = 1 Ampere
FormulaV = W / QVoltage = Work done / ChargeI = Q / tCurrent = Charge / Time
& Effect
Voltage is the cause of current (being an effect).Current is the effect caused by Voltage.
Measuring InstrumentTo measure the value of voltage by connecting it in parallel we use voltmeter.To measure the value of current by connecting in series we use ampere meter.
TypesAlternating Voltage and Direct VoltageAlternating Current (AC) and Direct Current (DC)
Magnetic FieldElectric Field (Electrostatic)
Produced byGenerator, Alternator and BatteriesVoltage and EMF
Drop and LossDue to Impedance (AC Resistance)Due to Passive elements
Series ConnectionUnequal in all components Equally distributed in all components
Parallel connectionMagnitude of voltage remain same in all componetsMagnitude of current vary in all components
Polarity ChangesAlternating Voltage changes its polarity and magnitude while it is remain constant in DC.Alternating Current changes its polarity while Direct Current does not changes its polarity.
ExistenceVoltage can exist without current, as it is the cause of flowing charge.Current does not exist without voltage, as voltage is the main cause to flow current except theoretical superconductor.

Also Read: Difference Between Resistor And Capacitor

What you need to know about voltage and current

  1. The voltage is the difference of the electrical charges between the two point of an electrical field, whereas the current is the flow of the electrical charges between the point of an electrical field.
  2. In a series circuit, the magnitude of voltage remains different in all the component of the circuit whereas the magnitude of current remains same.
  3. The SI (International unit of the standard) unit of the voltage is volts, and the SI unit of the current is amperes.
  4. The voltage is represented by the symbol V whereas the current is represented by the symbol I.
  5. The voltage can be defined as the ratio of the work done to the charge, whereas the current can be described as the rate of the charge to the time.
  6. The voltage generates the magnetic field around it whereas the current generates the electrostatic field around it.
  7. The voltage is the difference between the point in an electric field, whereas the current is caused by the flow of the electron in the electrical field.
  8. The voltage drop mainly occurs due to the impedance of the circuit whereas the current drop occurs due to the passive element (like a resistor) of the circuit. The impedance is the obstruction induces by an electrical circuit to the flow of an electrical current when the potential difference is applied across them.
  9. The voltage is measured by an instrument called a voltmeter whereas the current is measured by the ammeter.
  10. The polarity of the alternating voltage remain changes and due to this alternating voltage, the alternating current induces. But the polarity of the direct voltage remains constant, and their effect induces a direct current.
  11. The one volt is equal to the 1 joule/coulomb whereas the one ampere is equal to the one column/second.
  12. In the parallel circuit, the voltage at all the branches of the circuit remains same whereas the current is unequally distributed in the circuit component.
  13. The voltage is the cause of the current whereas the current is the effect of the voltage.