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

2532 Views

See similar Physics A Level tutors

Related Physics A Level answers

All answers ▸

What is Kirchoff's first law?


A sample of pure gold has a density of 19300 kgm^-3. If the density of a gold nucleus is 1.47x10^17Kgm^-3, discuss what this implies about the structure of the gold atom. [4 marks]


2 identical trolleys of mass M(one is loaded with 2 blocks of mass m) are on a ramp inclined at 35° and are connected by a wire that passes around a pulley at the top of the ramp. They are released and accelerate accordingly. Show that a=(mgsin35°)/(M+m).


What is meant by an excited atom?


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