Atoms are Connected by Force

If an atom is more than 99 % free space,

how come are we so solid?

considering the fact that objects, and therefore our body, for that matter, are smooth and SOLID……so when i poke someone, the force that stops me from digging my finger in is NOT because something else is occupying the space that I’m trying to displace but rather because of electrostatic force?!!!!……

…..the relative strengths of various forces….how can the force be because I’m trying to displace something, when the force that stops my skin from probing into any surface is electrostatic (I’m thinking in terms of a threshold of distance beyond which my human strength is insufficient to overcome the electrostatic force of repulsion between the atoms on the surface in question and my skin)

We are used to thinking of “things”, but in the subatomic world, it turns out that everything is based on forces….. if you have ever played with magnets……when you try to bring two strong magnets together, with the same poles of the magnet the nearest, you will find it really difficult to get them very close to one another. It is like that in atoms.

The electrons – which we now consider to have zero size!! – move in the area around the nucleus so very fast, that it is as if they are everywhere at the same time. You can think of a very VERY fast guard dog, barking at every intruder. The magnetic field of the electrons in one atom or molecule will repel the magnetic field of other electrons in other atoms or molecules. The electromagnetic force is a very powerful force, much MUCH more powerful than gravity, and it is the electromagnetic repulsion that gives us a sense of solidness.

It is an idea that takes getting used to!

…… you are trying to displace something, but the forces you encounter are electromagnetic….. ‘just’ electrostatic force. To give you some idea of just how immensely powerful the electromagnetic force is:  If the force of gravity was as powerful as the electromagnetic force, the Earth would only need to weigh 5 trillionths of a gram to have the gravitational effect it has. The electromagnetic force is 10^39 more powerful than gravity.

Of course, materials are built up of atoms and molecules, and these are sometimes arranged in lattice structures – like crystals – and sometimes just in clumps and piles. But the ‘edges’: what we see as smooth surfaces, are usually tiny moonscapes if you look at them though a powerful enough microscope.

And all of that structure usually has a bit of flexibility. The atoms and molecules are linked to one another, again by electrostatic (es) forces. When the bits of your finger that are sticking out the most ,come very near the bits of the, say door handle that are sticking out the most, the “es” forces interact, and both the bits of the door and your finger distort out of the way a little….  the shape of the electron cloud around the molecules changes, and that exerts more force farther back, and the shape of those electron clouds too ‘compress’ or distort.

English: The graph of electrostatic force and potential energy between two positive charge. (Photo credit: Wikipedia)

But – imagining movement on a VERY small scale – eventually, the electron clouds cannot easily distort any more, and they start to push back harder. It is a little like pushing on a soft rubber sponge ball: at first it can compress, but there comes a point where it actually gets quite hard, and cannot easily be compressed any more.

We experience that as a force from the door handle countering our force, and gradually, the door handle starts to move, since the forces involved are greater than the spring in the handle can resist.

http://in.answers.yahoo.com/question/index?qid=20101011021309AAy3H8L

So even what appears to be empty space, is not.  If we could counteract that force, could we walk through walls?  Where is freedom in space?

Ελληνικά: Ηλεκτρική απωστική δύναμη (Photo credit: Wikipedia)