The situation is part of a mechanism I have been working on. It is used for a bicycle to automatically store and release energy with a spring. It is somewhat similar to a car clutch. 1. The problem statement, all variables and given/known data Two friction discs are rotating with different angular velocities and different torques. The discs come in contact with one another and press together with a certain amount of force. If you know: the initial angular velocity and torque of both discs the radius of both discs the normal force pressing the discs together the coefficient of friction for the friction surfaces, both static and kinetic could you find the change in the torque and angular velocity of both discs? If possible, how would one write an equation to solve this? If not, what information would be needed? 2. Relevant equations Ff=FNμ τiωi=τoωo 3. The attempt at a solution I have attempted to first take the average of the torques of the two discs. The greater the force of friction, the closer the output torque would be to the average. However, if I write that down mathematically, it would require the force of friction to be simply a ratio. It seems that the problem may require calculus, which I have never been taught yet. Using only my current understanding of physics, an attempt to solve the problem would most likely be guesswork.