What is ELECTRICITY? Is it a noun, a verb, or an adjective? If we are to delve into basic electronics, we might have to accept it as all three. Luckily we are not studying electricity as much as we are studying basic electronics. The basic electronics we cover will not only open the doors to advanced electronics but it will give us the tools to create rich, interactive work.

So where do we begin with basic electronics? Well, we return to elecricity. Perhaps by discussing it's attributes we can gain a better understanding of something terribly undefineable.


Voltage, Current, and Resistance


In breaking down the characteristics of electricity we begin with:

VOLTAGE (Electromotive Force)
Voltage is the ammount of energy required/spent to move a unit of positive charge from the negative to the posistive. (Recall the class discussion about the molecular level).

It is the "pressure" and is measured in Volts. When we measure voltage we measure between or across two points.


CURRENT
Current is the rate of electrical charge flowing through a point. It is measured in amperes or amps. Amperes are considered to move through a point.


RESISTANCE
Resistance is the reduction in CURRENT flow and is measured in OHMs. Anything that electricity moves through creates resistance, Even wire. Resistors come in many levels of resistance so that with the right resistor or combination of resistors we can affect the Voltage and the Current.

OHMS LAW


We use Current, Voltage and Resistance to construct OHM's law.

V = IR or Voltage = Current * Resistance

The combinations are:

I = V/R

V = I*R

R = V/I

These are the fundamental formulas of Ohm's law . Where V is the circuit voltage in volts, I is the circuits amperage in amps, and R is the resistance in ohms.