Planes and cars have problems braking if brakes are too hot. F1 teams complain also if brakes are too cold. What’s the reason behind so much variance?
Also, I have noticed, that basically any vehicle have smaller deceleration when moving fast than when moving slow. From elementary school physics – when I apply some force onto surface, I should get some amount of friction, so I don’t know why it changes. It this also related to the temperature, or is there unrelated mechanism behind it?
In: Physics
Planes and cars normally brake from a cruise. The brakes are cold when they start working, and the material they use needs to have high friction from cold for the brakes to work. The downside is, that the material that can brake from cold starts to melt, degrade and deform when it gets too hot. The upside is that they don’t need to brake so often so they can work like that.
A race car needs to brake every few seconds, if you use normal car brakes they’ll overheat super quick. You can drill holes in the brakes, add air channels and direct air at them to try and dissipate that heat to make them last a bit longer in that environment, and it will help. But also, because you’re braking every few seconds the brakes will always be hot, you don’t need them to work from cold any more. So race car brakes can use different materials that only start to work when hot, but also survive much higher temperatures. Thus, if the car goes too slow and the brakes get cold the drivers will complain because they don’t work so well anymore.
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