# Frictional wheels without slipping (gear system)

In the figure below it is stated that the friction force should always be greater than the tangential force in order to prevent slipping between two frictional wheels. My question is that if we apply newton's second law to that contact point won't the tangential force resultant points upwards with the direction of the friction? And thus the wheels have an opposite rotating direction?

• The diagram does not make clear which body is force $P$ applied on. Also consider, that Newton's law only applies on the center of mass of objects, and not any arbitrary point (at least in the calculation of acceleration). Feb 6 at 20:46