So I have a question where a gymnast starts on a high bar, fully extended at 180 degrees from the right horizontal. As the gymnast swings downwards (counter clockwise), this is in the positive direction, and her torque is positive. At the bottom though, (when she is at the vertical line, perpendicular to the floor), her torque becomes negative.. so at this point, does the rotation actually change direction? (in the clockwise direction)


I am confused because I can't picture seeing a gymnast rotating downwards in the counter-clockwise direction, then suddenly start rotating in the clockwise direction. So I have a few questions..

Is it possible for her torque to change direction, but for her to keep rotating in the same direction? (eg. torque acts clockwise when she is still rotating counter-clockwise?)
..and could this be a reason that she will start to slow down when she ascends, because the torque is in the opposite direction of her motion? (if that is even possible..)

Does the fact that she has gotten to the bottom of her swing and is starting to ascend have anything to do with this negative torque?

Can her velocity become negative at this point, and will this mean that the rotation has changed direction?


Any and all help is appreciated!!


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