Is it possible to move an object from rest at point A to rest at point B without any energy consumption?
Assume no friction, elastic losses, air drag resistance losses or otherwise. Rest is defined as static equilibrium. A pendulum at max height is not in static equilibrium
What do you mean energy consumption? If you're moving an object with mass, it will have energy.
If you mean moving an object without losing energy, look at situations where you convert gravitational potential energy to kinetic energy.
>Is it possible to accelerate an object without energy being "consumed"?
No.
No
No, but the energy consumed can be arbitrarily low.
Classically the answer is trivially no (moving from A to B requires some amount of displacement, therefore some amount of velocity, therefore some amount of acceleration, therefore some amount of energy); assuming of course that the object in question has mass and that the distance between A and B is nonzero.
So I assume the only way to make this question interesting is by involving quantum mechanics, warped spacetime or other such trickery?
I think when involving quantum mechanics, the problem needs to be restated somewhat because being “at point A” is not well-defined.
In quantum mechanics, maybe the question should be: Is it possible to change a particle's probability density without consuming energy?
>Is it possible to move an object from rest at point A to rest at point B without any energy consumption?
When you consider the entire system, energy is never consumed - it is always converted.
With no losses due to friction, heat, etc. you can get out exactly the amount of energy that you put into the object.
Consider an ideal car with an ideal electrical motor and ideal magnetic breaks. You can accelerate your car using an ideal internal battery, then break and recover all of that energy back into the battery. In principle, this car can keep accelerating and braking on a flat plane forever.
If your question is “without any energy conversion”, e.g. from chemical potential energy into kinetic energy and back, then it's not possible (as outlined). But since you only required that the vehicle be in static equilibrium, and chemical potential energy is not a mechanical force, this car abides by your rules.
How low? What are the constraints on how low? Can it be arbitrarily low?
In a perfect dissipationless world is there any reason we can't have an object with a perfect spring that unwinds flinging the object forward, the forward motion now winds up the spring slowing the device to a stop.
Perhaps we have some detent or bistable that locks into place once the spring has wound back up.
>How low? What are the constraints on how low? Can it be arbitrarily low?
Make the mass arbitrarily small or the point arbitrarily short
No. That would be contrary to everything thermodynamic, which is everything.
From pic related, you are asking if you can give something potential energy without losing any energy. Where does the potential energy come from, nowhere? Thats against the conservation of energy, which, to my knowledge, has never truly failed yet.
Op is gorilla tier shitposting.
>No. That would be contrary to everything thermodynamic, which is everything.
no it wouldnt.
fuck off retard
He didn't say the two points had to have different potential energy fegit
Technically, consumption in different from conversion, so...
Yes.
You could teleport between the two most distant ideas in your mind outside of energy and time. This is much more useful. Who cares about matter?
if you move it at a non-zero speed it will have a nonzero kinetic energy during that time.
even moving something in a frictionless vaccum in a finite time will take some energy
since you know words like friction and equilibrium you seem to be old enough to do the math yourself
No
Classically, an arbitrarily small amount of energy will make a particle move through an equipotential line indefinitely, assuming no friction
Are you merely pretending to be retarded?
Of course, but where are you going to get the rotating gravity field?
Is this a troll thread? Half the catalog is full of dumb questions like this. They're either very stupid or impossible to answer.
Yes, if point A and point B occupy the same space, or if the object is large enough to occupy both spaces at once. You aren't really moving it but it still kind of counts?
...
That is obvious. What I am wondering is if an object of non zero mass can move from an initial state of position X=0 Velocity=0 to another final state of X=d Velocity=0 where d is some arbitrary distance greater than 0, with no energy lost or added in the process.
If not, what is the theoretical minimum amount of energy one must expend for a given mass and distance?
OP here, I am serious.
I'd say it depends on what you consider to be "at rest", because if the object begins moving on its own then it wasn't in static equilibrium in the first place, and if it is then it will require some energy, even if infinitely small, to fall from the edge of A
See
sure, if a asteroid passes arbitrarily close to the earth, little pebbles on the big pebble will be moved by earths gravity
Technically in QM there's a thing called virtual particles, which essentially are particles that are created out of nothing, using the Heisenberg uncertainty principle to "create" energy for a short period of time by "borrowing" it from the principle. These particles (since both a particle and an antiparticle is created) could move and then annihilate. So in theory, yes
Wouldn't switching between regenerative braking and motoring dissipate some energy?
And what proof do you have that this would actually be the case?
A = B
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>Wouldn't switching between regenerative braking and motoring dissipate some energy?
Well, yes, in principle, physically inputting a command of any sort could be considered as requiring energy, but I don't think that's within the scope of this question because it's essentially negligible. (Pressing a button is not comparable to, say, accelerating a 1000kg vehicle and driving across a continent - which is what that button press could imply)
Ultimately if you want to get rid of all physical input of any sort, then the system needs to autonomously trigger itself; and the action for doing this has to come from somewhere. Since we're forced to be in static equilibrium, one of the ways you could avoid it is with a digital oscillator that has a nonzero magnetic or electrical potential energy. (After all, we're ignoring losses due to heat/radiation/etc.)
>And what proof do you have that this would actually be the case?
Take an existing car with regenerative brakes, and remove all of the factors causing external energy losses (heat, drag, radiation etc.)
Since you've removed energy loss by definition, the only possible conclusion is the system's energy is constant, ergo you could keep on going forever.
OP here, I consider the switching to be non negligible. And I still don't buy that the switching the brakes dissipates no energy.
Also I doubt that the charging circuit would be dissipationless, even with ideal components
Well, feel free to come up with a simpler model in which you don't need to worry about a billion different factors.
Aquinas and also
Bump
>Would it be possible to do something prevented by the laws of physics if we could somehow suspend the laws of physics?
No, you wouldn't be able to keep it on the track.