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2.0 General Questions

Ohm's Law defines the relationships between (P) power, (E) voltage, (I) current, and (R) resistance. One ohm is the resistance value through which one volt will maintain a current of one ampere.


    •( I ) Current is what flows in a wire or conductor like water flowing through a pipe. Current is measured in (A) amperes or amps.

    •( E ) Voltage is the difference in electrical potential between two points in a circuit. It's the push or pressure behind current flow through a circuit, and is measured in (V) volts.

    •( R ) Resistance determines how much current will flow through a component. Resistors are used to control voltage and current levels. A very high resistance allows a small amount of current to flow. A very low resistance allows a large amount of current to flow. Resistance is measured in ohms.

    •( P ) Power is the amount of current times the voltage level at a given point measured in wattage or watts.


The relationships of Current, Voltage, Resistance, and Power are given here:

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A great example provided by Jason See Profile can be found Here

by Macy See Profile edited by Riss_Centaur See Profile
last modified: 2006-02-06 18:38:22

You can find several calculators online, a few examples can be found at
The 12Volt.com
Electrician.com
MCsquared.com
CrownAudio.com
You can find many other useful calculators at 101Science.com

by Macy See Profile

rockotman See Profile suggested a demo download from Orcad that allows you to run their software to do layouts and analysis.

by Macy See Profile

There is a good link at Xtronics and another from Samengstrom.com.
DannyG.com offers a nice little calculator to find Resistor Values from color codes.

Resistor Color Codes are also being discussed Here.

Click for full size


by Macy See Profile
last modified: 2006-02-07 11:20:19

You can find a list of resources recommended by our forum members Parts, Parts!.

by Macy See Profile

Some of our members posted several links where you may obtain printed circuit board fabricators, you can find that list here »Printed Circuit Board Fabricators .

by Macy See Profile