EMF, Potential difference, Electrical power, Types of supply

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Electromotive force:-
  •       Causes an electric current to flow in an electric circuit.


Potential difference:-
  •            Difference between electrical potential of two points which tends to cause flow of electrons between them.
  •            Electrical potential of a point can be measured by the amount of work done in bringing a unit positive charge form infinity to that point.
  •              Unit : volt (V).

Electrical power:-
  •          Work done by the electrical instruments per a unit time.
  •           P= W/t
  •           Unit: Watt






Types of electrical power supply:-

1.       DC Supply:
  •           Polarity of the current/voltage/power of a source remains same with respect to time.
  •          Example: Current available from batteries and solar cell is of DC Current.


2.       AC Supply:
  •           Magnitude and polarity of the current/voltage/power of a source changes periodically with respect to time.
  •     Example: Electrical power output from the alternators.

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