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Why did the electric bike flip when its power got cut off by the alien in Nope (2022)? Wouldn't its wheels continue spinning as it loses speed until it comes to a stop?

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  • Yes, but it would stop within its own length. That is how electric vehicles work.
    – Chenmunka
    Commented Aug 27, 2022 at 17:52
  • @Chenmunka I think that would make a good answer
    – user96544
    Commented Aug 28, 2022 at 2:22
  • I don't understand what it means by "stop within its own length". I'm assuming electric bike works like a regular bike except the engine's powered by battery rather then gasoline. If the rear wheel locked due to stalled engine, wouldn't the bike skid instead of flip? I would understand it if the front wheel locked and the bike flipped. Or is it different with electric bike - front and rear wheels are both linked directly to the engine and both would lock if engine stalled?
    – bassfocus
    Commented Aug 28, 2022 at 2:32

1 Answer 1

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Electric vehicles do not freewheel like a petrol vehicle when the power is disconnected.

The wheels continue to rotate but now they turn the motors, generating electricity to feed back into the battery. This removes the kinetic energy from the wheels and the vehicle, thus producing very effective braking. This regenerative braking is harnessed in most cases to extend the range of the vehicle.

In the same way that an electric vehicle can easily do 0-60 in 2 seconds, it can stop 60-0 in about 1 second.

Thiz also explains why many electric cars don't have a brake pedal. Just lift off the accelerator and you stop.

A sudden and violent stop on an electric bike could easily cause it to flip over.

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  • I get the logic in this answer as far as it explains a sudden deceleration. But, is there still a gap in that this answer doesn't explain the flip, which would require some rotation moment? Where does that come from? Is it as simple as: the deceleration force is rearward and happening at the surface, below the centre of gravity, while the momentum of the rider is forward and above the centre of gravity? Feel free to incorporate if that sounds right.
    – user96544
    Commented Aug 28, 2022 at 12:35
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    Is it really true that taking your foot off the accelerator in an electric car is the equivalent of applying maximum breaking power? Last time I used an electric bike was a long time ago but releasing the accelerator merely caused the motor to stop supplying power and the bike coasted. If you want to stop quickly you had to apply the brakes. Also, for a bike to flip due to braking that would require the braking force to be on the front wheel and usually the motive force is on the rear wheel (although that doesn't have to be universal).
    – Eric Nolan
    Commented Aug 31, 2022 at 11:04
  • This answer is very incorrect. As of now, every production electric car has a brake pedal. And the motor in an electric bike is connected to the rear wheel; braking the front wheel is entirely mechanical. This answer is also wrong in the context of the film: The alien shuts down all electrical activity, so there would be no regenerative/braking force while under that influence.
    – feetwet
    Commented May 9, 2023 at 14:52

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