Resistors

Resistors / resistances

Resistors (resistances)

Resistors are passive electronic elements with the main characteristic of electrical resistance, therefore. It has a specific function - to limit the flow of electric current in a circuit. Resistors, also known as resistors, are extremely widely used in electronics and electrical engineering.

They are among the most common components in electrical circuits. Most electronic devices contain a large number of them. They are made from various chemical substances in the form of compact elements, or from a coiled wire with a high specific resistance. Resistors are also used in integrated circuits, especially in analog devices, and can also be integrated into hybrid or printed circuits.

Ohm's Law and Measurement

The resistance of a resistor is measured in ohms (Ohm) and indicates how difficult it is for current to flow through it. Higher resistance means more difficulty for current to pass, while lower resistance allows current to flow more easily.

One of the basic laws associated with resistors is Ohm's Law. It states that the voltage (V) across a resistor is proportional to the current (I) flowing through it and the resistance (R) of the resistor itself. The formula that describes this law is V = I * R.

Resistors can be made of a variety of materials, with metals such as carbon, metal strip, or tantalum being the most commonly used. Their size and shape may also vary depending on the application.

Color codes and designations

Most often, their value is indicated using the so-called color code - a series of color designations that carry information about the value of the resistor as well as its tolerance. However, the color ring resistance identification method can be calculated directly without measurement. Ring color marking is mainly applied to cylindrical resistors, such as carbon film resistors, metal film resistors, metal oxide resistors, fuses and protective wire resistors commonly used color ring resistance can be divided into four rings and five rings, usually four rings. Among them, the first two rings of the four-ring resistance are numbers, the third ring represents the number multiplied by the resistance value, and the last ring is the error (tolerance). The first three rings of the five-ring resistance are numbers, the fourth ring is the number multiplied by the resistance, and the last ring is the error. The fault is usually gold, silver and brown. The error in gold is 5%, the error in silver is 10%, the error in brown is 1%, the error in colorless is 20%, and there are random errors represented in green. The green error is 0.5%.