A resistor means an element that restricts or limits the current flow. And the resistance of that element is measured by using ohms

ohm=

1 =1V/A

Kilo-ohms == 1k=1000 ohms

Mega-ohms==1M= 1,000,000 ohms

Resistors are manufactured with a different set of values and to represent those values they used the concept of color bands (1 band resistor, 4 band resistor, 5 band resistor)

A 4 band resistor will contain 4 different color stript and a 1 band resistor will contain 1 color strip similarly remaining band resistors will contain strips with their respected colors to represent a particular value

A 0 resistor will have only one band and the color of that band will be black, usually, it is used as a wire with no resistance

#### Resistor color code table

## How to calculate a 4 band resistor value

The above resistor shows a 4 band resistor with colors as (brown, green, red, gold) and to find the value of the resistor we can use the above resistor color code table from above

The brown color code is 1

The green color code is 5

The red color code is 2

15X=1500=1.5k ohms

For 4 band resistor take the first two-color code values as it is, and, for the third color take the multiplier value from the resistor color code table and leave the fourth color value the golden color strip is a tolerance value

#### Watts in resistors

During the design process of a circuit, it is equally important to know the resistor ohms value and its watts

**Why?**

Because the individual color code value of a resistor can have different watts resistors with the same ohms

For example, a 1.5k ohms resistor can also be available in different watts(5 watts, 2 watts, 1 watt, ½ watt, ¼ watt, 1/8 watt)

½ watt resistor means it is a half of 1 watt

¼ watt resistor means it is a quarter of 1 watt, which is 0.25W

You can easily figure out the watts of a resistor by looking at its size the large the physical size of the resistor the large the watt it will have

Suppose if the circuit required a resistor of 1.5k ohms with 2 watt

Then in that case, if you have used the resistor of 1.5k ohms with ¼ watt as a result the resistor will burn out with heat

So having the correct watts of a resistor is also important to the circuit designing

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