Understanding Kinetic Friction: Solving Problems in 3D Physics Simulations

[Brainv2.1beta]

I am trying to create a 3d physics simulation and the first "problem" I have encountered is implementing realistic friction. Now, I was told by some professor that the faster an object is traveling the less friction that it has, however, I have not been able to find the appropriate equation/s on the net. I know the basic friction equation, F=uN. However, this is only useful for static applications; I need to learn the formula for kinetic friction, and how to apply it to non-static variables (eg. speed-=frictionequation.)

 

[Doc Al]

In the usual ("standard" or Coulomb) model for dry friction between surfaces, kinetic friction is given by $\mu_k N$ and is independent of velocity. When you start adding in air resistance you'll quickly get speed-dependent forces.

 

[Brainv2.1beta]

So your saying that professor I mentioned was incorrect? At least this makes coding easier.

By the way, I am making rolling sphere physics.

 

[Doc Al]

So your saying that professor I mentioned was incorrect?

Why don't you ask the professor what he meant?

 

[Brainv2.1beta]

Why don't you ask the professor what he meant?

Can't, I talked with him last at a science convention overseas.

 

[Doc Al]

Then pick up any freshman physics book and read what it says about kinetic friction.

 

[Brainv2.1beta]

Then pick up any freshman physics book and read what it says about kinetic friction.

Yeah yeah I'm not in school anymore though and the library's a long walk...google doesn't really count...