Define various terms of AC waveform
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Waveform :
A waveform is a graph of AC quantity against the time.
Instantaneous value :
Instantaneous value is the value of AC quantity is define as the value of that quantity at the particular instant Time.
Cycle :
A complete set of positive and negative part of AC quantity is known as cycle.
Time period or periodic time ( T ) :
Time period or Periodi time is defined as the time taken of AC quantity to complete one cycle.
It's unit is second
T = 1/F ........... Where F = Frequency.
Frequency :
The number of cycle completed in one second is known as frequency that is denoted by F
It's unit is Hz ( hertz )
F = 1/T
Amplitude :
The maximum value or a pic value of an AC quantity is known as amplitude.
It is denoted by Vm for Voltage.
And
It is denoted by Im for Current.
Peak to Peak voltage :
The peak voltage is the voltage major from baseline to its peak level.
It is also called as amplitude,
and which is denoted by Vm or Vp
Vp - p = 2Vm
RMS Value :
It is also called as root mean square.
The RMS value of an AC current is equal to DC current that is required to produce same amount of heat as produced by AC current.
RMS value = 0.707 x Maximum value.
Vrms = 0.707 x Vm = √ 2 Vm
Irms = 0.707 x Im.
The average value of an AC quantity is equal to average of all instance value over the period of half cycle.
Vavg = 0.637 x Vm
Iavg = 0.637 x Im
Form factor :
Form factor of AC quantity is ratio of RMS value to average value.
Which is denoted by ( Kf)
Form factor = RMS value/Average value
Angular velocity (W) :
It is define as the rate of change of Thera (θ) with respect to time.
W = dθ/dt
θ = 2π
W = 2Ï€/t
W = 2Ï€/(1/F) ........ ( T = 1/F)
Final formula,
W =2Ï€F
Some important formulas :
V = Vm Sinωt ..... ( ω =omega)
I = Im Sinωt
XL = 2Ï€FL Where ( XL = Inductive reactance )
XC =1/2Ï€FC Where ( XC = capacitive reactance )
Power Factor = CosΦ ...... ( Φ is called Phi)
P = VI CosΦ
P = I^2R
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