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

2488 Views

See similar Physics A Level tutors

Related Physics A Level answers

All answers ▸

A ball with radius 10cm is filled with an ideal gas at pressure 2*(10)^5Pa and temperature 300K. The volume of the gas is changed at constant pressure so that the radius of the ball is reduced with 1cm. Find the amount of gas and the new temperature


Show Maxwell's equations in free space satisfy the wave equation


A car of mass 1500kg is travelling at 10 ms-1 along a horizontal road. A brake force of 3000N brings it to rest. Calculate the deceleration of the car and the distance travelled by the car whilst decelerating.


Why do capacitors dis/charge suddenly and then slow down?


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