# How to find the resistivity of a resistor

The first thing one should know when reading a resistor is that the resistivity is measured in a unit called an ohm. It looks like the omega symbol in Greek.

Reading the resistors is actually quite simple due to a color code. Black represents 0. Brown is 1. Red is two. Orange is 3. Yellow is 4. Green is 5. Blue is 6. Violet is 7. Grey is 8. White is 9. This may seem complex, but it actually conforms to the colors of the rainbow, ROYGBV. Do not count Indigo. Indigo is a shade of blue and is therefore blue. Locate the gold part of the resistor. Hold the resistor so that the gold part is facing your right.

The first color band will be the tens place of the resistivity. The second band is the ones place. The third is not as simple. This one has a multiplier effect. The number you recieved from the first two are multiplied by 10 to the power of the third color. For example, if it is black, you have zero. Ten to the zero power is 1 and you have the number from the beginning. Brown is one, so that would multiply by 10. White would multiply by one billion. These resistors are extremely powerful and should only be used if you are in a power plant. Otherwise they waste money.

One final note. The resistivity of the resistor is only a part of the circuit. the wires have resistivity as well depending on their length and diameter.

Have fun reading the resistors, or at least do something productive with this knowledge.

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