Types of current waveforms & Features Of A.C. Waveform



Direct current means that the polarity of the e.m.f remains constant with time.

  • Current flows only in one direction, hence charge carriers flow in one direction only.

Types of direct current waveforms:

Types of dc waveforms


Alternating current means that the polarity of the e.m.f. changes with time.

  • Direction of current flow in the electrical circuits varies with time in a periodic manner.
  • Direction of the charge carriers’ flow changes back and forth.

Types of alternating current waveforms:

Types of ac waveforms

Features Of An A.C. Waveform

The sinusoidal alternating current can be represented by $I = I_{o} \, sin \, \omega t$

Sinusoidal alternating current

For a I vs T graph,

  • A cycle refers to one complete alternation of $I$
  • Period T refers to the time taken to complete one cycle of variation
  • Frequency f is the number of complete cycles of variation in one second
  • Instantaneous current refers to the current value at an instant of time.
  • Peak current value $I_{o}$ refers to the maximum current during the cycle or the amplitude of the a.c. signal.
  • Peak to peak value is the difference between the positive and negative $I_{o}$ value. For sinusoidal a.c., the peak to peak value is 2 $I_{o}$.

Back To Alternating Current (A Level Physics)

Back To A Level Physics Topic List



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