What is the root mean square voltage of an alternating current?

Since the voltage of alternating current, by definition, changes over time, it is helpful for physics to describe it using a sinusoidal curve. In this case, the amplitude of that sine curve becomes is what we would call peak voltage. But exactly due to the way the potential changes over time, it can be cumbersome to make calculations with this function.This is where the rms voltage comes in: if we were to find the direct current with the same performance as our A.C. can give us, what would its potential be? We can derive this using some simple integration, and the result for a sinusoidal curve will be Upeak/sqrt(2).

MB
Answered by Mate B. Physics tutor

2565 Views

See similar Physics A Level tutors

Related Physics A Level answers

All answers ▸

What is a moment?


The mass of the Earth is 6.0x10^24 kg and its radius is 6.4x10^6m, calculate the orbital speed of the moon around the earth, the orbit of the moon is a circle of approximate radius of 60R where R is the radius of the earth and a mass m.


How would our Sun's luminosity change if we increased its temperature 3 times?


What is the photoelectric effect and how does it provide evidence for the quantisation of electromagnetic radiation?


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2026 by IXL Learning