I drove onto the soccer field. I hit the gas. i no move.
Why? i was on mud. Mud has a lower coefficient of friction then grass or dirt, which is a problem since it is the force of friction that propels the car foward. The coefficient is not high enough to cause enough frictional force to move the car, thus the wheels turning in place. Now if I were to end here, my wheels would be turning, causing little damage, along with no movement.
Interstingly enough, my wheels dug 8 inch holes into the field. This happened because the coefficient of friction between the mud and my tires was higher the the coefficient of friction between the top layer of mud and the mud beneath it. Because of this, when my wheels turned, they pushed mud out behind them, which caused the wholes.
Hopefully you got that, if not, you'll survive. If you dont survive, congrads, your out of physics-c. :egg) <--- look. an egg.