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!

Homework Help: Equations on motion for spring

  1. May 8, 2012 #1
    1. The problem statement, all variables and given/known data

    the question asks for me to find the normal mode of the oscillator shown below
    where k1=3nm-1 k2=7.5 k3=39nm-1

    im having difficulty setting it up with gravity being the main problem

    diagram below

    2. Relevant equations

    3. The attempt at a solution

    equation of motion

    where m1 is the 2kg mass and m2 the 6kg mass

    m1[itex]\ddot{y1}[/itex]=m1g-k1y1 + k2(y1-y2)


    i think my equations of motion are wrong, hence why im not able to get the right matrices, im not exactly sure what though, im missing something elementary

    thanks for your help
    Last edited: May 8, 2012
  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