Torque Application: Simple Q&A Diagram

[yuiop]

Thanks for all your help - my understanding is improving :-)

As for finishing - this is just the start - I am writing a vehicle simulator
but both my maths and physics are weak - luckily I do at least know how to write software

I bought a Classical Mechanics book which I am working through now

and this question was related to calculating the lateral friction at the rear wheels based on the steering torque generated by the angled front wheels - that is why I was trying to avoid the pivot concept

I am still keen to find an alternative solution that avoids the parallel axis theorem etc.

If there is almost no friction such as when the car is on ice and the car is skidding, then it will turn around its COM as if that is the fulcrum. If there is normal friction between the road and the car and no skidding, then the center of the rear wheels axle, acts as the fulcrum. The back wheels effectively act as the bearings for the fulcrum or hinge and there is no lateral friction on the rear wheels due to the turning torque of the front wheels. The way to calculate the lateral friction of the rear wheels is to work out the "centrifugal force" of the turning car and the lateral friction of the rear wheels will be equal to the centripetal force required to keep the car moving in a circle and the pivot concept is irrelevant.

 

[WildEnergy]

Brilliant - that way of looking at it really helps :-) Thanks

 

[WildEnergy]

I found a very easy and intuitive way to solve this by considering the constant relation:
Atotal = Aforce + Atorque
Aforce = F / m
Atorque = F * d * d / I
now it is easy to work out the force at the contact point