A resistor is an electronic component that is used to resist or oppose the flow of electric current in a circuit. It is a passive component, which means that it does not require any external power source to function.
Resistors are typically made of materials such as carbon, metal, or wire-wound materials. They come in a variety of shapes and sizes, and are marked with a color code or numerical value that indicates their resistance. The unit of resistance is ohms, symbolized by the Greek letter omega (Ω).
Resistors are commonly used in electronic circuits to control the flow of current, limit the amount of current that flows through a circuit, and provide a specific voltage drop. They can also be used to divide voltage, generate heat, and perform other functions.
Overall, resistors are essential components in electronics and electrical engineering, and are used in a wide range of applications in devices such as computers, televisions, radios, and more.
A thermistor is a type of resistor that changes its resistance in response to changes in temperature. The word “thermistor” is derived from the words “thermal” and “resistor”.
Thermistors are made from semiconductor materials such as ceramics or polymers, which have a negative temperature coefficient (NTC) or a positive temperature coefficient (PTC) of resistance. NTC thermistors have a negative coefficient of resistance, which means that their resistance decreases as their temperature increases. PTC thermistors have a positive coefficient of resistance, which means that their resistance increases as their temperature increases.
Thermistors are commonly used as temperature sensors in electronic circuits. They are very sensitive to changes in temperature and provide accurate readings over a wide temperature range. They are often used in applications such as thermostats, temperature controllers, and temperature-compensated circuits.
Thermistors can be used to measure both high and low temperatures, depending on the type of thermistor used. They are also very reliable and have a long lifespan compared to other types of temperature sensors.