Timeline for Why doesn't a braking car move backwards?
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12 events
| when toggle format | what | by | license | comment | |
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| Dec 10, 2018 at 0:49 | comment | added | user208769 | UK English: Saying that "the wheels lock, and then you skid" is absolutely correct. Most non-drivers don't need to consider the cause, only the effect - so tend to talk about skidding rather than the wheels locking, which would only be broached in a much more technical discussion. But most people get taught about their wheels locking during driving lessons, in discussing the role of ABS. | |
| Dec 6, 2018 at 18:35 | comment | added | wedstrom | I've heard "locked up the breaks" or similar. | |
| Dec 6, 2018 at 18:32 | history | edited | spcan | CC BY-SA 4.0 |
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| Dec 6, 2018 at 12:52 | comment | added | StayOnTarget | I think in English the term for wheel locking would be "skidding". | |
| Dec 6, 2018 at 12:51 | comment | added | StayOnTarget | (paragraph 4) The brakes not only dissipate the rotational KE of the wheels but the much larger translational KE of the entire mass of the car. | |
| Dec 6, 2018 at 2:43 | comment | added | Jay | Finally that force of the master cylinder applied to the discs which are bolted to the hub exceeds that being applied by the engine to the flywheel causing the hub to move or advance. Thus the overall result is 0 net motion in any direction depending on the angle of the incline, wind and other conditions in the environment including but not limited to gravity and electromagnetic forces. | |
| Dec 6, 2018 at 2:34 | comment | added | Jay | It's actually quite puzzling to me why struts and suspension don't also contribute to the electrical regeneration but that's another topic. | |
| Dec 6, 2018 at 2:32 | comment | added | Jay | And i think its because the master cylinder is applying constant pressure through the calipers to the hub which holds the car still preventing it from moving most likely even if you the accelerator and the brakes at the same time due to the weight of the car and amount of pressure being applied by the master cylinder. (Unless you got a powerful engine or crappy brakes) | |
| Dec 6, 2018 at 2:23 | comment | added | Jay | Some designer wheels freely spin while the vehicle is stopped. I would add usually to the part about while the car is advancing and technically we are talking about the hub not the wheels and yes some hubs just disengage. Finally some hybrids use the thermal energy and the other properties depending on the caliper and hub arraignment to regenerate the battery. | |
| Dec 6, 2018 at 0:26 | comment | added | senderle | I like this answer because it gets at the fundamental process. Sure, a property of friction is that it is a motion-resisting force, but this shows why. You could imagine a whole range of other kinds of energy transformations that would all produce the same behavior. It's useful, for example, to compare this behavior to the behavior of a regenerative braking system. Rather than being transformed into heat, some of the car's kinetic energy is transformed into chemical potential energy. In both cases, the car stops moving because it effectively runs out of kinetic energy. | |
| Dec 5, 2018 at 18:34 | comment | added | Eric Lippert | "Wheel locking" is maybe not 100% idiomatic but any English speaker would understand what you meant; after all, ABS stands for "anti-lock braking system". The more common term for losing tracking such that the wheels are not rotating but the car is still moving is "skidding". If you are skidding on purpose to gain a speed advantage in cornering, that's "drifting", and if you're drifting to make a circular track on the ground for fun, that's "doing donuts". English is weird. wikihow.com/Do-Donuts | |
| Dec 5, 2018 at 13:40 | history | answered | spcan | CC BY-SA 4.0 |