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: Parallel Axis Thereom to find angular velocity

  1. Jul 21, 2011 #1
    1. The problem statement, all variables and given/known data
    A meter stick is freely pivoted about a horizontal axis at the 94.7 cm mark. Find the (angular) frequency of small oscillations, in rad/s

    2. Relevant equations
    [itex]\Sigma[/itex] [itex]\tau[/itex]=I [itex]\alpha[/itex]
    3. The attempt at a solution
    5.37 rad/s
  2. jcsd
  3. Jul 24, 2011 #2

    The torque equation you wrote should be: -mgd*sin[itex]\theta[/itex]=Id^2[itex]\theta[/itex]/dt^2
    (you forgot the 'd' on the left-side.)

    For small angles, sin[itex]\theta[/itex][itex]\approx[/itex][itex]\theta[/itex]

    The torque equation can then be rewritten as:


    This is a common differential equation that arises in physics, and it describes a type of oscillatory motion known as "simple harmonic motion".

    The period is:


    The angular frequency can be easily found from here.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook