Difference Between Alternating Current (AC) & Direct Current (DC)

Both AC and DC describe types of current flow in a circuit. In direct current (DC), the electric charge (current) only flows in one direction. Electric charge in alternating current (AC), on the other hand, changes direction periodically. The voltage in AC circuits also periodically reverses because the current changes direction.

Key differences between Alternating Current and Direct Current

  • -The current which changes its direction at a regular interval of time such type of current is called alternating current. Direct current is unidirectional or flows only in one direction.
  • -The charges in the alternating current flow either by rotating a coil in the magnetic field or by rotating a magnetic field within a stationary coil. In direct current, the charges flow by keeping the constant magnetism along the wire.
  • -The frequency of the alternating current is 50 to 60 hertz depends on the country standard, whereas the frequency of the direct current always remains zero.
  • -The power factor of the alternating current lies between zero to one, whereas the power factor of the direct current always remains one.
  • -The alternator current is generated by the alternator. The direct current is generated by the generator, battery and cells.
  • -The load of the alternating current is capacitive, inductive or resistive. The load of the direct current is always resistive in nature.
  • -The alternating current can be graphically represented through different irregular wave shape such as triangular wave, square wave, periodic wave, the saw-tooth wave, sine wave, etc. The direct current is graphically represented by the straight line.
  • -The alternating current transmits over a long distance with some losses, whereas the direct current transmits over very long distances with negligible losses.
  • -The alternating current is converted into direct current with the help of rectifier whereas the direct current is converted into alternating current with the help of the inverter.
  • -Few substations require for the generation and transmission of the alternating current. Extra substations require for the transmission of direct current.
  • -The alternating current is used in industries, factories, and for the household purposes. The direct current is mainly used in electronic equipment, flash lighting, hybrid vehicles, electroplating, electrolysis, for exciting the field winding of the rotor, etc.