Results 1 to 1 of 1

Math Help - Physics: A rolling penny

  1. #1
    Aug 2008

    Physics: A rolling penny

    If you start a penny rolling on a table with care, you can make it roll in a circle. The coin leans inward with its axis tilted. The radius of the coin is r, the radius of the circular path it follows is R, and velocity is v. Assuming that the coin does not slip, find the angle theta that the axis makes with the horizontal

    The answer is given as

    I always have problems figuring out how to start the problems, but the answer usually becomes clear after I get past the first step. The only equation that I can think of that would help is I=.5mb2, but since mass isn't mentioned in the problem it seems useless.

    So far what I have done is draw a free body diagram of the penny with the force of the penny's weight acting straight down, the normal force acting straight up, and frictional force directing it toward the center of the circular path it follows.

    Where would be a good place to start?
    Last edited by davesface; October 15th 2008 at 02:06 PM.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Got a physics question or interested in physics?
    Posted in the Math Topics Forum
    Replies: 16
    Last Post: February 3rd 2014, 01:56 AM
  2. Replies: 0
    Last Post: December 29th 2009, 08:08 PM
  3. Rolling a die
    Posted in the Statistics Forum
    Replies: 3
    Last Post: November 2nd 2009, 06:53 AM
  4. how do solve quantum physics or physics equations
    Posted in the Advanced Applied Math Forum
    Replies: 2
    Last Post: March 26th 2008, 04:33 AM
  5. physics, acceleration, physics problem
    Posted in the Math Topics Forum
    Replies: 3
    Last Post: September 29th 2007, 03:50 AM

Search Tags

/mathhelpforum @mathhelpforum