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Question

There are two cones, which sides touch each other. One of the cones is rotating by angular velocity v1, the other cone can rotate free. What is the angular velocity v2 of the second cone, if:

a)Coefficient of friction between surfaces of cones is a constant and it is equal to a
b)Coefficient of friction is equal to a = kv, where v is a relative speed between the surfaces of cones.

Answer 1

V1=V2 Since;
1. The mass of the free-rotating cone is not given there is no inertial resistance.
2. The normal to the surface is not given but assumed to be sufficient to make use of friction.
3. The cones are assumed to be geometrically identical