1. The problem statement, all variables and given/known data I am solving a question that asks for, what's the minimum coefficient of friction required for a cylinder to roll without slipping? Where the cylinder has a force F acting on its center. 2. Relevant equations And 3. The attempt at a solution From the way I understand it, the only torque acting on the cylinder is the torque from friction, since the torque from force F is acting at the center, thus resulting in 0 torque. But the resource I'm looking at assumes that torque from friction is not the only torque acting on the cylinder. But it doesn't explain why. Where are the other torques acting from?