Ball colliding with an arm of an object that can rotate to it's axis

[Xcrypt]

http://imageshack.us/photo/my-images/195/spinner.png/
^this is the object/spinner I am referring to.

I am trying to code a physics based minigolf game in which a ball should be able to collide properly with the spinner object and the arms of it.
However I am lacking in physical knowledge to do so.

This is the model I currently have:

1) When the ball hits the spinner, a point gets defined where the ball hits the spinner. Of this point on the spinner, there is a tangential velocity bound to it which I have put in a vector.

2) Then, I projected the ballVelocityVector onto that tangentialVelocity Vector, and get a new vector: ballProjectedVelocityVector

3) After that, momentum gets defined:
ballProjectedMomentumVector = ballProjectedVelocityVector * ballMass
spinnerPointMomentumVector = pointTangentialVelocityVector * spinnerMass [probably where it goes wrong?]

4) Then new velocities get defined for the ballProjectedVelocityVector and the spinnerPointTangentialVelocityVector
Using:
va = [C_r*m_a*(u_b-u_a)+m_a*u_a+m_b*u_b]/(m_a+m_b)
where:
v_a is the final velocity of the first object after impact
v_b is the final velocity of the second object after impact
u_a is the initial velocity of the first object before impact
u_b is the initial velocity of the second object before impact
m_a is the mass of the first object
m_b is the mass of the second object
C_r is the coefficient of restitution (which I have set for a near-perfect non-elastic collision (0.05) )

5) The spinner gets a new angular velocity: (the new spinnerPointTangentialVelocityVectorLength / distance from that point to the axis of the spinner)
The ball gets a new velocityVector: (the new ballProjectedVelocityVector + (the old ballVelocityVector[projected onto the vector perpendicular to the projected velocity]) )

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However, this model I am using is not quite accurate, since if 'the point where the ball hits the spinner' is closer to the axis, the MORE angular rotation the spinner will get with this model.
Does anyone know what I am doing wrong / what steps I should take to determine the proper new angular velocity of the spinner after collision and the new velocity of the ball after collision?

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In explaining, please make try to do so so I can understand, because although I am very interested in physics and learning, my current knowledge is still very low.

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Thanks a lot for the help! :)

 

[LightHero]

One thing to keep in mind is that rotational momentum is different from linear momentum. The angular momentum of the spinner can be calculated using the following equation:L = I * ω where L is the angular momentum of the spinner, I is its moment of inertia, and ω is its angular velocity. When the ball collides with the spinner, the angular momentum of the spinner will change. In order to calculate this, you need to calculate the linear momentum of the ball. This can be calculated using the following equation:p = m * v where p is the linear momentum of the ball, m is its mass, and v is its velocity. Once you have the linear momentum of the ball, you can calculate the change in angular momentum of the spinner. This can be done using the following equation:ΔL = p * r where ΔL is the change in angular momentum, p is the linear momentum of the ball, and r is the distance from the point of contact to the axis of rotation of the spinner. Now that you know the change in angular momentum of the spinner, you can calculate the new angular velocity of the spinner using the following equation:ω = (L + ΔL) / I where ω is the new angular velocity, L is the initial angular momentum, and I is the moment of inertia of the spinner. Finally, you can calculate the new velocity of the ball by using the following equation: v = p / m where v is the new velocity of the ball and p is the linear momentum of the ball. I hope this helped!