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!

Rotational Motion (Inclined Plane)

  1. Jan 5, 2008 #1
    [SOLVED] Rotational Motion (Inclined Plane)

    Hi Everyone!
    My question is: A solid cylinder and a solid sphere are resting on top of a inclined plane. Using mathematics, which object would reach the ground first. Given: I (cylinder) = 1/2mr ^2 and I (sphere) = 2/5 mr ^2.

    I know that the sphere would reach the ground first because of its mass distribution, but I am not quite sure how to show it mathematically. My teacher said a problem like this will show up on my test Monday!

    Please help!!
     
  2. jcsd
  3. Jan 5, 2008 #2

    Kurdt

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    What is the energy of a rotating solid?
     
  4. Jan 5, 2008 #3
    I think what kurdt's suggesting is to try using energy methods.

    p.s. Are you taking AP Physics C?
     
  5. Jan 6, 2008 #4
    CALCULATE THE KINETIC ENERGY OF THE CYLINDER AND THE SPHERE AT THE BOTTOM OF THE PLANE...AND THEN FIND WHICH OF THE TWO HAS THE GREATER VELOCITY....

    THE ONE WITH GREATER VELOCITY IS THE ONE WHICH COMES DOWN EARLY..

    USE THE FORMULA..

    mgh=1/2mv^2(1+k^2/r^2)

    K(RADIUS OF GYRATION)==I/M
     
  6. Jan 6, 2008 #5
    Thanks, but I figured it out!
    P.S: What is AP Physics C??
     
  7. Jan 6, 2008 #6

    Kurdt

    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Advanced Placement college board course. Its an American thing I believe.
     
  8. Jan 6, 2008 #7
    No I am not.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Rotational Motion (Inclined Plane)
Loading...