Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

About the movement of a cube and a sphere on a plane

  1. Nov 1, 2012 #1
    A spherical or cylindrical object would roll on a plane.
    However,object with other shapes(e.g. A cube or a retangular object) would slide on a plane.
    Why?
     
  2. jcsd
  3. Nov 1, 2012 #2
    Because:-
    When a cylinder/sphere rolls, it's centre of mass stays at the same height so only a little bit of energy is needed to move it.

    But to 'roll' a cube, you have to lift the centre of mass over the corner. That takes a lot of energy. If you push a cube very hard and give it plenty of energy, it will roll. (Think of dice)
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook