## Saturday, July 27, 2019

### intro to electronics - part 1 - the terms

I plan to introduce the subject as if it was a day one student being taught. This may to basic for some but a good review has never hurt me. So we begin.

When the world was evolving towards our modern electronic wonder man kind had no knowledge of basic sciences. The alchemist was trying to turn lead to gold and doctors were bleeding their patients in an effort to cure them. Then the battery was invented. The battery was used to shock frog legs and make them jump! Electroplating was developed ...............

As the periodic table was developed man kind became aware of the characteristics of the elements and a new term was coined. The gram molecular weight which in a strange way becomes the basic for our world of electricity and electronics.................

To electroplate a gram molecular weight of a material requires a specific numbers of electrons. If we define this number of electrons as a coulomb it could be stated "when one gram molecular weight of XXXXX is deposited by the electroplating process  one coulomb of electrons flowed through the solution."..........

A quick search would reveal the number but the actual number is not important. We use the unit to define our other terms, that is why it helps to know what it is.

Ohm's law says when we apply 1 volt of potential across a 1 ohm resistor we have 1 ampere of current flow. One coulomb of electrons flowing through a circuit in 1 second is 1 ampere. One ampere (amp) of current produces 1 watt of power in a 1 ohm resistor. So the units were developed based on current flow and the potential to produce it through a specific value of resistance.

So we can use Ohm's law to find voltage (E), current (I) or resistance (R) in a circuit.
E=I*R
R=E/I
I=E/R