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!

Rotational Inertia in two cylinders

  1. Mar 25, 2014 #1
    Calculate the kinetic energies of two uniform solid cylinders, each rotating about its central axis. They have the same mass, 1.25 kg, and rotate with the same angular velocity, 235 rad/s, but the first has a radius of 0.18 m and the second a radius of 0.73 m.

    I got 12112188.868 for ω, and 0.050625 for I

    I have been using I=mr^2, and .5*Iω^2

    I plugged everything in with out changing any units, and got 1906125390.62499825 for the small one, which i know to be wrong. Then I thought I remembered something my teacher said about multiplying the radians by 2pi, and then I plugged all the numbers back in and got another large number.
  2. jcsd
  3. Mar 25, 2014 #2
    nvm, ran out of time. getting help from my teacher tomorrow
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted