Peak-to-Peak, RMS Voltage, and
Power
Where’s my notes
from last week!
Alternating Current Defined
• In alternating current (ac), electrons flow
back and forth through the conductor with
some periodicity.
AC Vocabulary
Power in AC
Finding the Effective Voltage
• The voltage used in power calculations in ac
is the equivalent dc voltage value that
would do the same amount of work (or
heat) .
• A simple average of ac voltage is not quite
good enough.
• A weighted average called Root Mean
Square (RMS) is more accurate.
Okay – Important Points about
RMS
• RMS is the equivalent value of dc voltage
to do the same work.
• RMS is used in Power and Ohms Law
formulas.
• The RMS voltage is 0.707 times the peak
voltage.
• AC volt meters measure RMS voltage!!!!!
Converting Peak Voltage to RMS
Remember:
How to Use the Math
How to Use the Math
How to Use the Math