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: Vector math for precession?

  1. Feb 24, 2006 #1
    Trying to find the vector math for gyroscopic precession - all web sites I've seen that deal with analysis don't include direction of rotation as a vector and I can't find a discussion in my texts on the subject.

    The question I'm trying to answer is whether two opposite rotating discs of equal speed/mass will cancel precessional forces. This is being looked at in terms of a motorcycle wheel patent to make steering easier at high speed.

    Everybody seems to have their own opinion on the subject and so it seems the only way to settle the question is with the math.

    Thanks for any help
  2. jcsd
  3. Feb 24, 2006 #2


    User Avatar
    Science Advisor
    Homework Helper

    Your angular velocity vector lies along the axis of rotation (perpendicular to the rotating wheel) in the same direction as the angular momentum vector (cross product of the radius vector and the linear velocity vector at some given instant of time).

    What force is providing the external torque that's causing the precession?

    Here's a link on precession that may help: HyperPhsyics - Precession Torques
  4. Feb 25, 2006 #3
    Thanks Bob - the references mentioned will give me a little more info as well
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook