Motivation
Is it still possible to set the rotating body in motion, because the current is feeded on the axes? I found my answer, It’s not about how and where the current is supplied, only how and where the torque is made possible.
The current is only fed in and out axially.
The counter torque can only be applied via the current collector on the disc edges.
M and the dashed M indicate the torque and counter torque.