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I am aware that electrons are moving in an empty space so basically there is no friction to slow it down and its velocity stays the same. However where did the electron get its energy from in the first place(during the creation of the universe"Big bang"). Plus when we "touch" there is no physical contact.The electron's negative charges oppose themselves and repel each other.Basically I'm floating now in my chair.However when electrons push against each other doesn't that mean there is a force acting on the electron and pushing it away from its trajectory.So why doesn't everything fall apart when we sit on a chair or grab a pencil,why wont the electrons fall from trajectory and get caught by the protons.

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Related: physics.stackexchange.com/q/23797/2451 –  Qmechanic Jan 1 '13 at 3:49
    
Hi and welcome. Please could you ask just one question at a time? At the moment you've got at least three questions, and that means this isn't a single real question. As such it's liable to be closed. –  EnergyNumbers Jan 1 '13 at 12:03
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However where did the electron get its energy from in the first place(during the creation of the universe"Big bang").

All energy, and remember energy and mass are related by E=m*c^2, that exists in the universe existed after the first minutes of the Big Bang . For t=0 plus an interval after it where gravitational forces predominate, i.e the realm of General relativity, energy conservation is not a well defined measure.

Matter as we know it appears after 10^-6seconds or so. Energy conservation holds but particles can appear and disappear according to the well studied interactions of elementary particles. A specific electron may have been created and thus acquired mass either after the first moments of the Big Bang or after some elementary particle interactions. In matter as we know it electrons are bound to nuclei which have positive charges, having given up any primordial kinetic energy they had when they were captured in quantized orbits about the nucleus.

Plus when we "touch" there is no physical contact.

All matter as we know it is neutral, atoms are neutral. Nevertheless there exist spill over electric and magnetic fields from the necessary asymmetry of most atoms. These generate the Van der Waals forces which keep atoms in solids and also repulse overlap attempts, since the orbits of the electrons around the nuclei can only be distorted by everyday pressure of matter on matter. One can define "physical contact" as the electromagnetic interaction from the left over electric fields of the neutral atoms. All contact is electromagnetic in origin in the world we live in and sense with our five senses.

Electrons can be freed from their orbits about the nucleus. There can be the triboelectric effect, which creates static electricity and they gain kinetic energy by the rubbing. Or strong electric fields can extract outer electron and free them, again by electromagnetic exchanges. Then they gain their energy from the electric field we supplied.

when electrons push against each other doesn't that mean there is a force acting on the electron and pushing it away from its trajectory.So why doesn't everything fall apart when we sit on a chair or grab a pencil,why wont the electrons fall from trajectory and get caught by the protons.

For the same reason that electrons orbiting the nucleus do not fall in the nucleus. It is called quantum mechanics, which is the mechanics that rules in the elementary particle range, and electrons are elementary particles. Atoms are stable because their electrons have to orbit around them in specific energy states and cannot be dislocated by simple pressures ( which are also electromagnetically transmitted) and scatterings.

As you will see if you read the links to really answer these questions satisfactorily one needs to study physics at some depth.

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You have a lot of questions here, and they show you really need to read up on some basic physics, but here goes with some simple answers:

  • Where did the electron get its energy from in the first place? What energy do you mean?
  • Why doesn't everything fall apart when we sit on a chair or grab a pencil,why wont the electrons fall from trajectory and get caught by the protons? You need to look at both attractive and repulsive forces. Negative charges are attracted to positive charges, so electrons are attracted to protons, but once particles start to get very close to each other it gets very difficult to push them further. You can do it, but it takes a lot of energy. Have a look at fusion bombs or stars for example.
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