1. Not finding help here? Sign up for a free 30min 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!

What does 'simple harmonic motion' mean?

  1. Aug 6, 2007 #1
    What does 'simple harmonic motion' mean? By definition, it describes any periodic motion that is the result of a restoring force that is proportional to displacement. What does 'periodic' mean here? It means recurring at equal intervals of time? Ususally, the example of SHM is virating mass-spring system. But the definition of SHM is sort of according to the formula, so I don't really get its essence. Is simple harmonic motion simply a back-and-forth motion over the same path? In the 'wave', it says that a wave whose source vibrates with simple harmonic motion is called a sine wave. Once again, what does SHM really mean?
  2. jcsd
  3. Aug 6, 2007 #2
    It's as the name describes: some sort of motion that has a defined harmonic (frequency), and one that can be described with a relatively simple equation.

    -Periodic does mean recurring at equal intervals of time.
    -I don't know if back and forth motion is the best descriptor, but yes it is about a motion that can be modeled by waves.
    -The wave can be either sine or cosine.

    The examples, of course, include a mass and a spring, a pendulum, and even atomic vibrations.
  4. Aug 7, 2007 #3


    User Avatar
    Homework Helper

    The position of the oscillator can be described mathematically by a sine (or cosine) varying function of time. What can be simpler than that?
  5. Aug 7, 2007 #4
    Its a simple back and forth motion. The equation (y=asinwt or y=acoswt) describes an oscillating point on the y or x respectively axis of a circle with radius 'a' centered at the origin.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?