1. Not finding help here? Sign up for a free 30min 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 momentum multiparticle system

  1. Nov 8, 2007 #1
    1. A rotating uniform-density disk of radius 0.9 m is mounted in the vertical plane. The axle is held up by supports that are not shown, and the disk is free to rotate on the nearly frictionless axle. The disk has mass 3.6 kg. A lump of clay with mass 0.4 kg falls and sticks to the outer edge of the wheel at the location < -0.81, 0.392, 0 > m. Just before the impact the clay has a speed 9 m/s, and the disk is rotating clockwise with angular speed 1.00 radians/s.

    (a) Just before the impact, what is the angular momentum of the combined system of wheel plus clay about the center C? (As usual, x is to the right, y is up, and z is out of the screen, toward you.)
    (b) Just after the impact, what is the angular momentum of the combined system of wheel plus clay about the center C?

    2. L = Ltrans + Lrot
    L = r x p
    L = |r||p|sin(theta)
    moment of inertia of a disk = (1/2)mr^2



    3. Ok so i tried solving this by finding out the angular momentum of the disc which is <0,0,-1.458> but I cannot figure out the total before the impact. I don't think I solve this without the angle of impact but there has to be a solution. i think that afterwards the angular momentum of both will just be the same as the moment before the impact because momentum is conserved right?
     
  2. jcsd
  3. Nov 8, 2007 #2
    i figured out that the direction is in the negative y cause the clay falls on the disc but i still can't figure out either before or after the impact momentum
     
  4. Nov 8, 2007 #3
    figured out the momentum after the impact <0,0,1.458> still clueless about before the impact
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Angular momentum multiparticle system
Loading...