- #1
Kibbel
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Homework Statement
A rotating uniform-density disk of radius 0.7 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 location A, < -0.42, 0.560, 0 > m. Just before the impact the clay has a speed 6 m/s, and the disk is rotating clockwise with angular speed 0.34 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.)
Homework Equations
moment of inertia for a disk is (mr^2)/2
Angular momentum = Iw
Angular momentum = R(perpendicular)*momentum*w
The Attempt at a Solution
okay so its l split it into two angular momenta, of the clay, and of the wheel and added them together
wheel 1/2*m*(r^(2))*w + R(perpendicular)*momentum of clay
momentum of clay = mass * velocity of clay
so I got .5*(3.6)*(.7^2)*<0,0,-0.34> + 0.42*(6*.4)*<0,0,1>
is this right? i think it is, but I am not sure if that's set up correctly..