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Old 12-15-2008, 11:45 PM   #4 (permalink)
jamesqf
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Quote:
Originally Posted by Peter7307 View Post
Nearly forgot...one factor in rainy day mileage is less resistance from the tyres which are "lubricated" by the water on the road. This is also why stopping distances are greater in the we than in the dry.
Huh? Think about that for a bit. First, when it's wet, the tires have to do work pushing the water out of the way, thus higher rolling resistance and lower fuel economy (as confirmed by the mpg gauge in my Insight). Second, the stopping distances are greater only because the lubricating effect of the water lowers the amount of braking force that can be applied before you transition from rolling friction to sliding. That is, if you brake with the same force, and it's not enough to cause you to go into a skid, the stopping distance will be the same.
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