A.C. power supply voltage amplitude questions

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SUMMARY

The discussion centers on calculating the root-mean-square (Vrms) and average potential difference (Vav) for an AC power supply with a voltage amplitude of 45.0 V. The calculated Vrms is 31.82 V, derived from the equation Vrms = Vmax / √2. The average potential difference Vav is zero due to the symmetrical nature of the sinusoidal waveform, which results in equal positive and negative areas over one complete cycle. This conclusion is supported by examining the graph of alternating voltage versus time.

PREREQUISITES
  • Understanding of AC power supply principles
  • Familiarity with sinusoidal waveforms
  • Knowledge of root-mean-square calculations
  • Ability to interpret voltage-time graphs
NEXT STEPS
  • Study the derivation of Vrms for different waveforms
  • Learn about the implications of average voltage in AC circuits
  • Explore the concept of phase difference in AC signals
  • Examine practical applications of Vrms in electrical engineering
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Students studying electrical engineering, educators teaching AC circuit theory, and professionals working with power supply systems will benefit from this discussion.

bluesteels
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Homework Statement
The voltage across the terminals of an ac power supply varies with
time. The voltage amplitude is V = 45.0 V. What
are (a) the root-mean-square potential difference Vrms and (b) the average
potential difference Vav between the two terminals of the power supply?
Relevant Equations
Vmax= square root 2*Vrms
I know that the answer for A is 31.82. But when i look up B why is it zero? can someone explain please

thank you
 
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bluesteels said:
Homework Statement:: The voltage across the terminals of an ac power supply varies with
time. The voltage amplitude is V = 45.0 V. What
are (a) the root-mean-square potential difference Vrms and (b) the average
potential difference Vav between the two terminals of the power supply?
Relevant Equations:: Vmax= square root 2*Vrms

But when i look up B why is it zero? can someone explain please
What do you think the answer to (b) should be?
 
bluesteels said:
Homework Statement:: The voltage across the terminals of an ac power supply varies with
time. The voltage amplitude is V = 45.0 V. What
are (a) the root-mean-square potential difference Vrms and (b) the average
potential difference Vav between the two terminals of the power supply?
Relevant Equations:: Vmax= square root 2*Vrms

I know that the answer for A is 31.82. But when i look up B why is it zero? can someone explain please
Look at a graph of (sinusoidal) alternating voltage vs. time. Can you use the graph to explain why the average is zero?
https://www.teamwavelength.com/download/alternating-1024x597.png
 
Orodruin said:
What do you think the answer to (b) should be?
i know that it zero cause i look it up but idk why
 
bluesteels said:
i know that it zero cause i look it up but idk why
No, what do you think it should be without looking it up. Without referring to any authority, what do you think it should be?
 
bluesteels said:
they didnt give me time?
Another way to ask the question is:
What is the average voltage over each complete cycle?​
Does that help?

Also, you might want to reply to @Orodruin's Post #6!
 

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