Define the terms related to a.c. supply with waveform : i) Instantaneous value ii) Time period iii) Amplitude iv) Phase difference.

Define the terms related to a.c. supply with waveform : i) Instantaneous value ii) Time period iii) Amplitude iv) Phase difference. 
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1 Answer

Answer :

i) Instantaneous value: The instantaneous value is “the value of an alternating quantity (it may ac voltage or ac current or ac power) at a particular instant of time in the cycle”. 

OR 

 The value of alternating quantity (emf, voltage or current) at any particular instant is called the instantaneous value.

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ii) Time Period:

The time (in sec) required by an alternating quantity to complete its one cycle is known as time period. 

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iii) Amplitude: 

It is defined as the maximum or peak value attained by an alternating quantity during its positive or negative half cycle. 

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iv) Phase difference:

Phase difference is the difference in phase angle between two sinusoids or phasors. 

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