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!

Angular speed question

  1. Nov 6, 2009 #1
    1. The problem statement, all variables and given/known data

    A 320 N sphere 0.20 m in radius rolls, without slipping, 6.0 m down a ramp that is inclined at 25° with the horizontal. What is the angular speed of the sphere at the bottom of the hill if it starts from rest?

    2. Relevant equations
    I sphere= (2/5)mr^2
    atan=rα
    v=rω

    3. The attempt at a solution
    I tried first to use F∆x=(1/2)*[(2/5)mr^2]ωf^2-0(zero because it starts from rest) but then i realize i don't have a mass and now i don't really know what to do. any helpful hints or suggestions would be appreicated
     
  2. jcsd
  3. Nov 6, 2009 #2

    rock.freak667

    User Avatar
    Homework Helper

    At the top, it only has potential energy mgh. At the bottom, the energy is entirely kinetic. Do you see why you don't need the mass?
     
  4. Nov 6, 2009 #3
    so then can i just solve the eqn i was using and just ignore m?
     
  5. Nov 6, 2009 #4

    rock.freak667

    User Avatar
    Homework Helper

    No your equation is correct. Just what is the force F in [itex]F\Delta x[/itex]?
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Angular speed question
  1. Angular Speed question (Replies: 6)

Loading...