When your car goes into a skid it is common knowledge that you
are suppose to turn into the skid. In terms on Newton's laws
of motion, what is the physics behind this?
As long as your front wheels skid, you have no directional
control of the car. Turning your wheels in the direction of the skid
allows the wheels to start rolling in the direction of motion
again. Only once the wheels are rolling can turning them affect
the direction of the car. As long as the wheels are slipping
perpendicular to the plane of the wheel, they will not roll.
Friction is the major player here. If a car is moving across snow or
ice in any direction other than that which it's pointed, it is skidding
(or sliding), and a sideways load is being imposed against the tires.
This causes a lot of friction, even if the tires are allowed to turn.
By turning the front wheels into the direction of the skid, the front
wheels will become aligned with the direction of travel. No more
side load will be on the front tires, and they will roll freely again
(very little friction). But the back tires will still be sliding
sideways, and the greater friction back there will cause the back end
to trail directly behind the front end just like a badminton birdie,
thus the car straightens out. As the car straightens, the front wheels
must be kept aligned with the direction of travel, or a skid in the
opposite direction will quickly develop.
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Update: June 2012