I would like to know if a dielectric body is effected by the electric field with any force? Lets say I push a glass plate between two charged surfaces. The glasses dielectrical permeability(don't know if its the right word to use) is larger then the air's. Would there be some resisting force?

And with how big charge it is possible to practically load a body with?

Well, there are effects like piezoelectricity where deforming a crystal produces and electric field. I would imagine that the natural rigidity of the body would resist the motion, as would moving the charge distribution against an electric field.

I know about piesoelectricity, but that wouldnt count as much, I suppose. And if the glass would be moving with a constant speed, then there would be no deformation due to motion.

But then basically there is no force due to the fact that the body is moving into an electric field?

Think of a situation, where two electrically charged bodys are in earth gravitational field. Body A has a charge of -0,003C, and it is firmly attached to earth by non-conducting materials, so it won't lose its charge and it can't be moved from its place. Body B has a charge of +0,003C, a mass of 50kg, and is free to move.

In the initial positions, body B is 10m below body A.
The force between the charges is:
F₁=q₁q₂/4πεε₀r²

q₁=q₂=0,003C
ε=1
r=10m

F₁=809N

Since the body A is firmly attached, then the body B will be accelerated towards the body A, by the accelerating force of ~800N.
The acceleration will be: a=800N/50kg=16m/s²
If we subtract the gravitational acceleration, we will have an acceleration of a₁=16-10=6m/s²
Body B will have a net acceleration of 6m/s² towards body A - upwards.

Now, if the body B reaches the point where it is 5m away from body A, we push a non-conducting plate between them, which has a high dielectric permeability. Lets say the ε between the bodys will be 20.

r=5m
ε=20

the force between the two bodys will now be

F₂=162N

The acceleration towards body A will now be only a=160/50=3,2m/s²
And subtracting the gravitational acceleration a₂=3,2-10=-6,8m/s²

So the body B will be falling back down, with the acceleration of 6,8m/s² and increasing.

If the body B reaches the distance of 10m from the body A, we can remove the plate from between the bodies and ε=1 again, so body B will accelerate back towards body A.

I know I have left out the inertia of the body, and increasing acceleration, as the body B moves in relation to body A, but the principle remains.

Body B has moved back and forth with only work done by us is moving the plate between the two bodies and then away from there. We could probably use the movement of body B to gain energy from it, without doing almost nothing ourselves.

So what am I missing?

fo3:
So what am I missing?
That plate of some medium transforms the external electric field only inside it, not changing anything outside that plate!

That plate of some medium transforms the external electric field only inside it, not changing anything outside that plate!

oh.. then I had gotten it wrong..
but what if we'd replace the air surrounding the bodies by some other gas, which has a higher ε? Would that change anything for the two bodies?

Now you are on right way.

Is there any way to change gase's ε? Lets say, by heating it, for example? Adding/removing pressure? etc..

fo3,
usually all these actions lead to the changes of it.

But how much would the ε change? Its probably around +/- 0.5 or so, i suppose, not much more..

And the energy consumption in changing the gases dielectric permeability(or changing the gas) would be bigger then the possible gain from the up-down cycle of the charged body, yes?

Of course

Not that I was actually thinking otherwise..

Sorry, fo3,
I was sorry for you just from beginning of this thread: the idea was very good, not so trivial as in usual projects of a Perpetum Mobile...
Sorry, but Mother Nature is more clever than any of us...

Yeah, I've figured that.
But for me, thinking of things like these helps to better understand how nature works. I'd like to get the overall picture, before I'm going to study physics.
I mean, I knew from the beginning that this wasn't gonna work, but I was interested in why it would not. Maybe next time I come up with something like this, I can see the flaws myself.

fo3,
not bad, but do not allow this quest of Phantom to become your ...paranoia.
Somewhere (better sooner, than late) start study the Science. It is very tough process, but believe me it will bring you the much, much more pleasure than ... arrogant quest of Phantoms...
And believe me also in this: Science will show you the horizons that are much, much far away of any of those that are available for the common sense and domestic fantasy...

No worries there, I'm planning on studying physics right after highschool.. Which will be in about a year and a half. Its what I like, and what I'm apparently somewhat good at too, or so they say. I guess I'm lucky having the two in one combination.
And about the quest for the phantom, I would not say its a quest. nor for the phantom. I just seem to get some ideas every once in a while, that seem to work at the first glance. At least they seem for me. And the quest is to find out what is wrong with the ideas, so I could learn from it. Its easy to learn from errors, if the errors don't cause any damage.