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There are two main types of electric currents that are used in our daily life. They are
  1. Direct current
  2. Alternating current
Direct current (dc):
The motion of a positive charge from a higher to a lower electrical potential, or an electron from a lower to a higher electrical potential, causes current to flow through electrical circuits. Electrons travel from the negative terminal to the positive terminal of the battery. The unidirectional flow of electric charges causes the direct current (dc).
 
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dc circuit with graph
 
Sources of direct current:
1. A battery is one of the dc current sources that maintain a potential difference between the two ends of the wire.
 
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Battery
 
2. Solar cells and thermocouples are also the sources of dc.
 
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Solar cells and thermocouple
 
Uses:
Dc is used in a large number of electronic circuits.
Example:
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From clockwise: Cell phones, radios, electric automobiles and electric keyboards
Advantages of Direct current (dc):
  • Only direct current (dc) can be used for electroplating, electro-refining, or electrotyping.
  • Electricity can only be stored in the form of dc.