Define the various terms of AC wave form

 

# Wave Form

A wave form is a graph of AC quantity against time.

 

# Instantaneous value

It is the value of AC quantity is define as the value of that quantity at particular instant time.

 

# Cycle

A complete seat of positive and negative part of AC quantity known as cycle.

One Cycle = 2π Radian = 360 degree.

 

# Time Pried or Periodic Time (T)

It is define as the time taken by the ac quantity to complete one cycle.

 Its Unit is sec.

T=1/F    …….      Where F= Frequency.

 

 

# Frequency

The number of cycles completed in one sec is known as frequency.

It is Denoted by F

Its unit is Hz (hertz)

F=1/T

 

# Amplitude

The maximum value or pick value of ac quantity known as amplitude.

It is denoted by Vm for voltage & Im for Current.

 

# Peak to Peak voltage

The peak to peak voltage is voltage meager from base line to its peak level.

It is Also called as amplitude.

Denoted by Vm or Vp.

Vp-P= 2Vm

 

 

 

 

# RMS Value

The rms value of ac current is equal to the dc current that is required to produce same amount of heat as produce by AC current.

 

RMS value = 0.707 X maximum value

Vrms = 0.707 X Vm = √2 Vm

Irms = 0.707 X Im

 

#Average value

Average value of an AC quantity is equal to average of all insanities value over the pried 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

 

FF = RMS value/ Avg value

 

# Crest Factor or Peak Factor (Kp)

It is define as the ratio of maximum value to RMS value.

Kp = max value / RMS value

 

# Angular velocity (W)

It is define as the rate of change of theta(ϴ)

With respect to time.

W = dϴ/dt

ϴ = 2π

W = 2π/t

W = 2π/ (1/F)          ………. (T = 1/F)

   

W = 2πF

 

** Important Formulas **

 

# V = Vm sin wt

# I = Im sin wt

# XL = 2πFL

# XC = 1/ 2πFC

# Power factor = cosφ

# P = VI cosφ

# P = I²​R