a disk is initially rotating counterclockwise

I'm assuming that you're asking for an explanation of what would happen if a disk is initially rotating counterclockwise.

If a disk is initially rotating counterclockwise, it will continue to rotate counterclockwise unless acted upon by an external force. This is due to Newton's first law of motion, which states that an object in motion will remain in motion in a straight line at a constant velocity unless acted upon by an external force.

The direction of the rotation of the disk is determined by the initial angular velocity and the torque applied to it. If the torque applied to the disk is in the counterclockwise direction, it will continue to rotate counterclockwise with a constant angular velocity. However, if a torque is applied in the clockwise direction, the rotation will slow down, and the disk will eventually come to a stop before starting to rotate clockwise.

In summary, the initial rotation of a disk determines its direction of rotation, and the direction of the applied torque determines whether the rotation speeds up, slows down or changes direction.