Question

How is a resistor's value represented by color codes?

Answer 1

A resistor's value is commonly represented using a color code system. This system allows you to determine the resistance value of a resistor by interpreting the colors on its body. The color code system typically consists of four or five colored bands, each representing a specific numerical value or multiplier. Here's how it works:

The first and second bands represent the significant digits of the resistance value.
The third band represents the multiplier, which is used to scale the resistance value.
The fourth band (if present) represents the tolerance, indicating the allowable deviation from the stated resistance value.

For a four-band resistor, the color code order is as follows:

Band 1: First significant digit
Band 2: Second significant digit
Band 3: Multiplier (number of zeros to add)
Band 4: Tolerance (optional)

For a five-band resistor, the color code order is as follows:

Band 1: First significant digit
Band 2: Second significant digit
Band 3: Third significant digit
Band 4: Multiplier (number of zeros to add)
Band 5: Tolerance (optional)

Here's the color-to-value conversion for the color code:

Color - Digit Value:

Black: 0
Brown: 1
Red: 2
Orange: 3
Yellow: 4
Green: 5
Blue: 6
Violet/Purple: 7
Gray: 8
White: 9

Color - Multiplier Value:

Black: x1
Brown: x10
Red: x100
Orange: x1000
Yellow: x10,000
Green: x100,000
Blue: x1,000,000
Violet/Purple: x10,000,000
Gray: (not commonly used)
White: (not commonly used)

Color - Tolerance Value:

Gold: ±5%
Silver: ±10%
None (no band): ±20%

To use the color code, simply read the colors from left to right and combine the corresponding digit and multiplier values to get the resistance value. For example, if you have a resistor with bands: Brown, Black, Red, Gold, the value would be: 1 (Brown) 0 (Black) 2 (Red) * 100 (Gold) = 1000 ohms or 1 kilohm with a tolerance of ±5%.