Okay, thanks everyone for the help. When there is friction between the two surfaces, by Newton's third law, there should be a force exerted on the cone as well, so it seems that there should be a torque exerted on the cone. The rotational inertia of the ball about the axis of the cone's rotation...
This wasn't from a full problem, it is just a scenario that I thought of. I would just like to understand conceptually how the sphere will move and how the rotation of the cone affects it.
I am trying to understand the motion of the sphere in the image above, and I am a bit confused about the motion. How does the ball move down the cone? Will the rotation of the cone cause the ball to rotate with it, and which direction would the static friction be in? What does the path the ball...