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Re: Truck stopping distances?



Joseph Bellina wrote:

Second shot...there will be many more.

Its the same pavement, but not the same tires...but I don't think that
is a big issue. I suspect that the limiting factor is the temperature
of the brake pads, since if they get too hot, the friction coefficient
drops catastrophically.
So heavier trucks have more KE...takes more work to stop
them...generates more temperature increase, unless you limit the
rate of loss of mechanical energy by not braking so hard...hence the
longer stopping distance.

Rick Tarara wrote:
...
The brake force is not a function of the weight of the vehicles

Oh yes it is, because the engineers make it so.

The
difference in stopping distance between trucks and cars (as between
different makes of cars) is tied up with the brake design.

I doubt it. Engineers are pretty clever. If
better brakes would make a difference, they would
have done it by now.

In the case of
trucks, I also suspect the longer distances are due to a compromise between
safety and brake life--that is, while brakes could be designed to stop the
trucks in a shorter distance, they would tend to wear out much faster.

But they would only wear out faster during a panic stop;
during ordinary driving they would wear the same. So this
isn't a good argument.

I still think the strength-of-materials argument is the
most plausible.