Yeah, but how do we calculate the sliding length? I don't think I have calculated that before. Most of our problems have been rolling without sliding..
But the in problem a-c we assume that there are no friction, which makes the yoyo- roll with sliding.
So we cannot use energy-conservation to calculate ω. How can we then do it?
The Torque comes from the string force, right? But how do we calculate the angular velocity when it rolls and slides? Because then energy isn't conserved?
The friction isn't added before d, so is there angular acceleration even if it is slipping? Yeah, I´ll probably figure it out eventually :) thanks for your help!
in c) "What is the acceleration of the yo-yo? The angular acceleration?",
Is that just to trick us into believing that there is an angular acc, but in reality it is = 0?
Conditions:
* Point of contact -> not moving
* w = v/r (if it is rotating, then w > 0)
* There is a torque, which makes the yo-yo rotate. First I thought friction made it rotate, but it is the string tension, right?
But how is this related to problem a, about the conditions?
"Is it possible to roll down without slipping on the incline? Why/why not? (Carefully think of the rolling-without slipping conditions)."