Originally Posted by froggy81500
and that would be why? Wind chill will cause water to freeze, why wouldn't it affect cars?
Humans produce heat, cars don't (assuming the car is not running).
If both are outside (in the cold), the human will keep a body temperature higher than the ambient air. The car will slowly cool until it is the same temperature as the air surrounding it.
Wind chill makes us "feel" colder than the air around us because of the following thermodynamic principle: The greater the temperature differential between two mediums, the greater the rate of heat flow there is between them.
Let's assume no wind chill factor: We are at ~100 degrees and let's assume the air is at 10. As heat begins to flow out of us, the air immediately around us is warmed...let's say it's now 11 degrees. We can assume our body temperature remains the same as we're always producing heat. Since the air has warmed the temperature differential lessens, and the rate of heat transfer becomes less.
Add wind chill. The wind constantly circulates the surrounding air keeping it at a steady 10 degrees. The rate of heat transfer is allowed to stay at it's maximum given the situation, so more heat out per unit time = we "feel" colder. This is why it's often called the "feels like" temperature. The temperature outside is the same...but there's more heat flowing out of the body per unit time.
Cars are different from humans. As I stated, they don't produce heat. As such, their temperature declines until they match the outside air temperature. At this point, the temperature differential between the car and the air is 0. Heat transfer stops. The car cannot get any colder than the surrounding air.
Conclusion: Wind chill affects rate of heat TRANSFER. It has no bearing on the actual final temperature of any object or system. Wind chill will make it cool down faster, but its final temperature is the same with or without wind.
EDIT: Oh, and wind chill does not cause water to freeze, for reasons stated above.