*How to Understood of Determination of Maximum value and Frequency from EMF or Current Equations ?***The equation for the instantaneous values of Emf is given as**

*e = Emax sin 2Ï€ft = Emax sin 2Ï€ft*From the above equation we observe that

*i) the maximum value of an alternating EMF is given by the Coefficient of the sine of the time angle.*

ii) the frequency is given by Coefficient of time t divided by 2Ï€ii) the frequency is given by Coefficient of time t divided by 2Ï€

**Coefficient of time t**

i.e., f = ------------------------------

2Ï€i.e., f = ------------------------------

2Ï€

**Similarly we can also find the maximum value and Frequency of the current from the equation of instantaneous values of current.**

*Form Factor and peak Factor.*

__Form factor is defined as the ratio of effective value to the average or mean value of a periodic wave.__

**Mathematical form factor is given by the relation**

Effective Value

Form Factor = -----------------------------

Average valueEffective Value

Form Factor = -----------------------------

Average value

**The value of form factor for perfect sinusoidal, half- wave rectified full wave rectified, rectangular and triangular wave alternating Current are 1.11, 1.57, 1.11, 1 and 1.16 respectively.**

**Peak or crest or amplitude factor of a periodic wave is defined as the ratio of maximum or peak to the effective or rms value of the wave.**

*Maximum value*

i.e., Peak Factor, Kp = -----------------------

Effective Valuei.e., Peak Factor, Kp = -----------------------

Effective Value

**The value of peak of crest factor for Perfect sinusoidal , half wave rectified, full wave rectified, rectangular and triangular wave alternating Current are √2, 2.0, √2, 1 and**

**√3 respectively.**

__Phase and phase Angle__

*By phase of alternating Current is meant the function of the Time period of that alternating Current that has elapsed since the current last passed through*

Phase and phase Angle |

*).***the zero position of reference. The phase Angle of any quantity means the angle the phaser representing the quantity makes with the reference line ( Which is taken to be at zero degrees or radians). For example the phase Angle of Current I2 in fig. Is (-Î¦**

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