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: Plot motion of particle with constant speed and angular velocity

  1. Sep 27, 2012 #1
    Consider the problem of a particle sliding inwards with a constant speed c and starting at radius R=pc/Ω, on a platform rotating with a constant angular velocity Ω. Give a plot of the trajectory of the particle from r=R to r=0, for p=0.5, 1, 2, 6.


    I'm a little confused on how to do this. If there is no acceleration, then would the plot just be a series of straight lines? And should I plot r vs t even though time isn't mentioned at all?
     
  2. jcsd
  3. Sep 27, 2012 #2
    "Sliding" would imply that there is no friction with the platform, in which case the trajectory should indeed be a straight line - in an inertial frame of reference. Are you perhaps supposed to find the trajectory in the platform's frame?
     
  4. Sep 27, 2012 #3
    Also, how can something slide inward if it's moving in circular motion? Wouldn't centripetal force cause it to slide outward?
     
  5. Sep 27, 2012 #4
    That's why I think there is no friction.
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook