Electronics and Computers

As mentioned in the introductory lecture today's standard computers run on electricity, more specifically computers use the properties of electron flow (Amperes), electronic pressure (Voltage), and electro-magnetism to move data from one place to another, store data in chips, CD's and disk drives. Additionally, photon (light particles) controlled by laser technology and fiber optics is used to store and move data.

Electrons: All of you have had the experience of both seeing and feeling electrons.  For example: have you ever walked across a rug and then approached another person and had a spark jump from you to the other person?  When you crossed the rug your feet made contact with the electrons in the outer orbits of their atoms , kick them loose and they piled up on you.  All atoms have electrons orbiting around the center of the atom which contains protons.  Hydrogen has one proton and one electron. Hydrogen's atomic number is 1. Uranium has 92 protons in it nucleus and 92 electrons in orbit. 

If you could imagine another star coming close to our solar system, the first planet that would be captured in our solar system would be Pluto because Pluto is so far away from our sun that it can be knocked out of orbit very easily, whereas the inner planet Mercury would be the last to be captured by the rogue star.      

Essentially he same thing happens when you crossed the rug.  The reason that a spark jumps from you to the other person is that electronics push against each other and always want to go where there are fewer electrons.  The pressure that electrons exert to go where the density of electrons is less is called Voltage.  Voltage is the measure of electron pressure. 

Now if you know a person approaching you has just gathered an electrostatic charge by crossing a rug, the closer they get to you the more you try to avoid the pending shock.  When they get close enough to you, a spark (billions of electrons) flows from them to you and you jump.  The reason you did not get a shock from ten feet away is the resistance to electron flow (measured in ohms) of the air will not let the electrons flow to you until the distance is small enough that the electrons overcome the resistance of the air. Air is not a good conductor of electricity.  Ohms is the measure of resistance to electron flow of a conductor.  If we were to hand the student with a negative charge ( when an object has more electrons then surrounding objects it is negatively charged and the other objects are positively charged in relationship to it)  a cooper wire and then you touch the wire you will get a shock even if you are ten feet away because cooper is a good conductor of electricity and if electrons are offered a good conductor to flow they will. Ampere is the measure of the number of electrons that flow in a conductor.  

The father of the American Electrical Industry is Ben Franklin.  Most of you have seen pictures of Ben flying the kite that lighting strikes.  What Ben proved was that lighting was composed of electrons and that if provided a conductor the flow of electronics could be controlled.  With that knowledge he built lighting rods made of iron a good conductor of electricity  and made them available to everyone for free to prevent building that were struck by lighting from burning up.  The lighting would strike the lighting rod at the top of the building and flow down to ground without damaging the building.  All of today's modern building have lighting rods in them. Additionally all of today's modern electronic devices use the principal of  a conductor to move electrons.