(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A wad of sticky clay (mass m, velocity v), is fired at a solid cylinder (mass M, radius R). The cylinder is initially at rest and rotates on an axis through the center of mass. The line of motion of the projectile is perpendicular to the axis of rotation and at a distance d < R from the center.

Find the angular speed of the cylinder just as the clay hits the surface.

2. Relevant equations

Conservation of Angular Momentum

See: https://www.physicsforums.com/showthread.php?t=63404

3. The attempt at a solution

I did:

[tex]L_i = d m v_i[/tex]

[tex]L_f = d m v_f + \frac{1}{2} M r^2 \omega = d m r \omega + \frac{1}{2} M r^2[/tex]

[tex]L_i = L_f [/tex]

[tex]d m v_i = d m r \omega + \frac{1}{2} M r^2 \omega[/tex]

[tex] \omega = \frac{d m v_i}{(d m r + \frac{M r^2}{2})}[/tex]

Which isn't correct; it may have something to do with the momentum of the wad of sticky clay; the reason I used L = m v d is because d would be the moment arm but perhaps I'm confusing this with torque? What value of r should I use when the force isn't perpindicular?

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# Angular Momentum of clay ball

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