Hi all! I've got a problem which I can't solve for almost a week :-/ It's about simulating a car with some physics added. The things is that I cannot calculate the wheel angular velocity right. Let's assume that a car has no velocity and is using 7300 N (1st gear, 1000 rpm) of force on the rear wheels at the moment. Now I want to calculate the wheel angular velocity by integrating the wheel angular acceleration over time. Delta time is constant - 0.03s. I only need to calculate the acceleration: E=M/I M is my force multiplied with the wheel radius (0.34m) - 2482 Nm I is the inertia of the wheel - I assume it's about 4 kg*m^2 So the acceleration of the car is 620 1/s^2. This gives me a wheel angular velocity of 18.6 1/s. I think it's much too high, because when I calculate the engine rpm back from the wheel velocity I get: engineRpm=wheelAngularVelocity*ratio*60=18.6*6*60=6696 rpm It's much too big... What's the problem with my calculations? Btw. Sorry for my english :) I'll appreciate any help.