Electrical circuits lecture notes b. Tech

 
 
 
Susceptance
(symbolized 
B
) is an expression of the ease with which alternating current ( 
AC) passes through a capacitance or inductance 
Phase and phase difference: 
Generally all sinusoidal waveforms will not pass exactly through the zero axis point at the 
same time, but may be “shifted” to the right or to the left of 0
o
by some value when 
compared to another sine wave
. 
Any sine wave that does not pass through zero at t = 0 has a 
phase shift
. 
The phase difference or phase shift as it is also called of a Sinusoidal Waveform is the angle 
Φ (Greek letter Phi), in degrees or radians that the waveform has shifted from a certain 
reference point along the horizontal zero axis. In other words phase shift is the lateral 

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difference between two or more waveforms along a common axis and sinusoidal waveforms 
of the same frequency can have a phase difference. 
The phase difference, Φ of an alternating waveform can vary from between 0 to its maximum 
time period, T of the waveform during one complete cycle and this can be anywhere along 
the horizontal axis between, Φ = 0 to 2π (radians) or Φ = 0 to 360
o
depending upon the 
angular units used. 
Phase difference can also be expressed as a 
time shift
of τ in seconds representing a fraction 
of the time period, T for example, +10mS or – 50uS but generally it is more common to 
express phase difference as an angular measurement. 
Then the equation for the instantaneous value of a sinusoidal voltage or current waveform we 
developed in the previous Sinusoidal Waveform will need to be modified to take account of 
the phase angle of the waveform and this new general expression becomes.