Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Axial, torsional and pendulum modes of vibration(harmonic motion)

  1. Sep 18, 2007 #1
    1. The problem statement, all variables and given/known data

    This is more of a conceptual question rather than a problem with numbers.
    I was wondering if anyone new if there is a relationship between axial, tortional and pendulum vibration. The context is a mass hanging off a spring.

    ie will the natural frequency of vibration be the same for all 3 types given the same mass and spring constant?

    2. Relevant equations

    3. The attempt at a solution

    I tried an experiment and my apparatus is simply a mass hanging off the end of a spring. The only materials i had were an old school stop watch and a ruler so i had alot of difficulty getting any measurements. none fo which were any real use

    i know that the natural frequency of axial vibration is

    w(n)= sqrt(k/m)

    where k= spring constant
    m= mass
    w(n)= natural frequency

    i worked out the spring constant by graphing different masses versus deflection.

    I also know the formula for frequency of a pendulum with a mass and a string, but not with a spring.

    my common sense tells me that the natural frequency for all three modes of vibration will be the same when using the same spring and mass but i have no proof to back this up.

    Ive searched the internet and havent found anything relevant.

    Any hints would be great.
  2. jcsd
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted