Is friction the main factor in determining braking distance?

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    Braking Friction
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Friction significantly impacts braking distance, with less friction on icy or wet roads leading to longer stopping distances compared to surfaces with more friction, like rocky or sandy roads. The discussion highlights a common misconception that greater friction should always decrease braking distance. It clarifies that sliding friction and rolling resistance play different roles in vehicle dynamics. Additionally, driving techniques must adapt to varying road conditions, emphasizing the importance of understanding friction's role in braking. Overall, the relationship between friction and braking distance is crucial for safe driving practices.
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I was taught that in conditions where there is less friction, such as on icy or wet roads, the braking distance of a car, is less than if the car was traveling in conditions with more friction, such as when the road is rocky or sandy.

Although it makes sense intuitively, I recalled that friction opposes motion and not acceleration. So, for example, when a car travels to the right, and the driver applies the brakes, the car will still travel to the right, but just decelerate until it stops completely. Since friction opposes movement, and the car is still moving to the right when braking, then the direction of the friction force is to the left -- so shouldn't a larger friction force decrease the braking distance?

Thanks for your help!
 
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eddywalrus said:
I was taught that in conditions where there is less friction, such as on icy or wet roads, the braking distance of a car, is less than if the car was traveling in conditions with more friction, such as when the road is rocky or sandy.
There could be some confusion about sliding friction vs. rolling resistance here.
 
A.T. said:
There could be some confusion about sliding friction vs. rolling resistance here.

I'm not very knowledgeable when it comes to physics -- could you explain the distinction between the two for me? Thanks.
 
eddywalrus said:
I was taught that in conditions where there is less friction, such as on icy or wet roads, the braking distance of a car, is less than if the car was traveling in conditions with more friction, such as when the road is rocky or sandy.

Although it makes sense intuitively, I recalled that friction opposes motion and not acceleration. So, for example, when a car travels to the right, and the driver applies the brakes, the car will still travel to the right, but just decelerate until it stops completely. Since friction opposes movement, and the car is still moving to the right when braking, then the direction of the friction force is to the left -- so shouldn't a larger friction force decrease the braking distance?

Thanks for your help!

I don't know if you really meant this but the braking distance in ice is Greater than with more friction.
 
eddywalrus said:
I was taught that in conditions where there is less friction, such as on icy or wet roads, the braking distance of a car, is less than if the car was traveling in conditions with more friction, such as when the road is rocky or sandy.

This is most certainly wrong, or wrongly stated.

And the rules for driving vary with the type of road surface; you drive quite differently on gravel than you would on pavement.
 
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