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This effect can be prevented by gradually letting off the brake before reapplying it fully upon stopping, but few drivers and rapid transit systems are aware.

This is surprising to read. Everyone whose car I've ridden in knows to do that, and it's only in extremely urgent and unexpected stops where it's neglected. Also, when fully stopped, only minimal pressure should be necessary to keep the car still.

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There's definitely confirmation bias causing me to not notice stops where there isn't a jerk. And perhaps by the Baader-Meinhof effect you'll begin to notice them more frequently, too. But stops without any perceptible jerk are rare enough that when they happen I get an odd feeling of floating forwards like when the train beside your own at a station departs—perhaps it's because my subconscious, still anticipating the jerk, believes that I'm still in motion.

In some cars there's hysteresis in the brake pedal (perhaps caused by the booster or self-energizing system) that makes it hard to smoothly release the brake even when the driver tries to. But metros seem to increase their braking force—visible in standing passengers leaning progressively more—as speed decreases. Is there some physical cause to that?

> only minimal pressure should be necessary

I gathered that it was best practice to fully brake when stopped in case someone hits you, especially at a light where you might be rear-ended and roll into the intersection.

If rear-ended with your brakes engaged more of the impact energy will go into crumbling your car than if it's allowed to transfer into forward speed. If you see it coming, let go of the brake, and then step on it after impact. That's the advise I got.

It depends on if you're trying to minimize damage to your car, or the passengers. For a light impact where you aren't going to sustain any injuries it might be optimal to let off the brake. But if the accelerations are going to cause injury, then you would want to apply the brakes to minimize the acceleration of the car.

Strategy sounds legit but my concern would be that the (previously distracted) incoming driver attempts to dodge at the last second. Their car will hit your car with torque that could send it into oncoming traffic. But that angled impact also means less push in your car's forward direction, so maybe this concern is overblown.

> Everyone whose car I've ridden in knows to do that

I also do that, and don't know anyone who doesn't. I vaguely remember that I learned it in driving school, most likely because my driving instructor didn't want to be jerked around on the passenger seat for an hour every week.

Train/tram drivers here also usually do that in stations, except when they try to make up for delays, or when they have wrongly estimated the breaking distance.

Re train/tram drivers: Especially with more modern(ish) rolling stock that can also depend on how well the manufacturer has set up the braking system.

For one instance multiple units (especially electrically powered ones) commonly have computerised braking controls, often transition from dynamic to friction braking shortly before coming to a standstill, and might possibly have some sort of automatically applied parking brake.

If the manufacturer didn't properly adjust this whole system, the friction brake as it takes over for the last few kph might be applied with too much of a "bite" and therefore cause a jerky stop which even a skilled driver might not be able to fully prevent.

Older drivers seem not to know this, in my experience at least.

I think that's more of an indication of their fine motor control deteriorating with age.

> Also, when fully stopped, only minimal pressure should be necessary to keep the car still.

Why? To keep the brake fluid lines from bursting or something?

More pressure won't do any harm, it's just not necessary if you only want to keep the car still (on a flat road, in neutral, with nobody trying to tow you, etc.).

It's more tiring, however, which can be an important factor if you're taking a long trip.

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