Even though its Physics...The 'Angle' of the Object wheel would be still registered as normal..
So you could place a Variable or two on the wheel that for example is
Do a Every tick function
Every Tick-> set 'Wheel_initial_Angle' to Wheel Angle
Then then compare the Values every x seconds..dependant on the maximum required level of sensitivity..say every 0.5 secs.would need testing of course
Compare two values ->
[Wheel_updated_Angle > (greater than)Wheel_initial_Angle
Action Play your sfx or anything else..
you could set it up any number of ways
Boolean Variable" Wheel Rotate 36 degrees"
Is 'Wheel_updated_Angle 36 degrees greater than 'Wheel_Initial_Angle'
Set Boolean Variable" Wheel Rotate 36 degrees" TRUE
-> FIRE SFX
-> Reset variables..specifically up date the Initial and updated variables
There would be plenty of ways to do what you what
its just a matter of finding the BEST idea for you
This may take considerable testing phase ..but you would learn alot..:)
work for you?
first value would be the WHEEL angle and