Help me understand static and kinetic friction please

[knight92]

Hi, I understand that the static coefficient of friction dictates how much force is required to initiate motion/slippage and kinetic(dynamic) coefficient of friction dictates how much force is required to maintain motion/slippage. So considering a clutch with a friction and drive plate, what is dictating the rigid coupling when the there is no slippage it is transferring all the torque from the engine to the gearbox ?

Using uniform pressure theory the clutch's maximum torque capacity is:

T = (2/3)*u*N*Radius Gyration

where

u = coefficient of friction
N = Clamping force

If the car is in gear with clutch fully engaged (no slippage) then in this case the maximum torque capacity will be determined by the static or kinetic coefficient of friction?

Thank you.

 

[Chestermiller]

If the clutch isn't slipping, it's the coefficient of static friction that determines the maximum torque.

Chet