A resistor is a device having a planned resistance to the passage of an electric current. In electronic circuits, resistors are used to reduce current flow, adjust signal levels, and stop transmission lines.
You can also calculate the value of a resistor. Here is the resistor color code:
| Color | Digit | Multiplier | Tolerance (%) |
|---|---|---|---|
| Black | 0 | 100(1) | |
| Brown | 1 | 101 | 1 |
| Red | 2 | 102 | 2 |
| Orange | 3 | 103 | |
| Yellow | 4 | 104 | |
| Green | 5 | 105 | 0.5 |
| Blue | 6 | 106 | 0.25 |
| Violet | 7 | 107 | 0.1 |
| Grey | 8 | 108 | |
| White | 9 | 109 | |
| Gold | 10-1 | 5 | |
| Silver | 10-2 | 10 | |
| (none) | 20 |
On a resistor, there are 3-5 colors. Ignore the last 2 colors for now; focus on the others. Based on the “digits” part of code, translate it and you’ll get a 1-digit, 2-digit, or 3-digit number. Now focus on the second last color. Based on the “multiplier” part of the code, translate the number to a power of 10. Multiply the two numbers together. The result is the value of the resistor (in ohms).
But what about the last number? This calculates all the possible values. The one you previously got is the average of all the possibilities. To calculate, translate the last color based on the “tolerance” section. If the number you got was x and the tolerance percentage number is y, then the lowest possible resistance value would be x-(xy/100) and the highest possible value would be x+(x(y/100).
