A question about a body moving in horizontal circular motion

I have some related questions about a body moving in uniform horizontal circular motion:

The body moves with a constant angular velocity on a rough horizontal surface. It is attached to a string that is attached to a fixed point on the surface. The body revolves around that fixed point. If the body is continuously in contact with the surface, in which direction will friction act and what type will it be (static or kinetic)?

Now what if it moves with constant angular acceleration? In which direction will friction act?

What if the body is on a rough inclined plane undergoing circular motion?

• friction is (supposed to be) opposite to the direction of motion (this means is opposite to tangent of the path) and depends on body weight, then it can be analysed to perpendicular and horizontal components (the perpendicular would be associated with the force that keeps the object in orbit) Commented Oct 27, 2014 at 15:04
• what if a string is attached to the body. then tension provides some centripetal force. what about friction?? Commented Oct 27, 2014 at 15:11
• The friction is opposed to the direction of motion - but there are other forces acting on the object to maintain either constant angular velocity, constant acceleration, and/or when it is moving on a plane. I wonder if you need to rephrase your question a bit... Commented Oct 27, 2014 at 15:12
• i rephrased it. is it clear now?? Commented Oct 27, 2014 at 15:15
• what type of friction? the body is moving right? Commented Oct 27, 2014 at 15:15