1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Can someone please explain what the parallel axis theorem is?

  1. May 30, 2014 #1
    Can someone please explain what the parallel axis theorem is?
     
  2. jcsd
  3. May 30, 2014 #2

    UltrafastPED

    User Avatar
    Science Advisor
    Gold Member

  4. May 30, 2014 #3

    sophiecentaur

    User Avatar
    Science Advisor
    Gold Member

    The PAT tells you how the MI of an object changes when you use an axis that's not through the cm. Obviously, the mi will be higher (imagine trying to turn a disc around a point on its circumference - or even on the end of a long massless pole)
    There is an analogous situation with standard deviation of a probability distribution. It is a 'second moment', in the same way. The standard deviation from the mean is less than the rms deviation from some other value. Also, the power of an AC waveform is greater when it has a DC offset component. Same sums for all three, basically.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook