Resistors

Resistors are electronic components that limit or regulate the flow of electrical current. The main types of resistors include:

1. Fixed Resistor: 

Provides a constant resistance value, used in circuits to limit current. Examples include:

   (i) Carbon Composition Resistor: 

Made of carbon particles and a binder, known for its durability and cost-effectiveness, but with less precision.

   (ii) Metal Film Resistor: 

Offers better precision and temperature stability, commonly used in high-accuracy applications.

   (iii) Wire-Wound Resistor: 

Made by winding metal wire around a core, designed for high-power applications due to its ability to dissipate heat.

2. Variable Resistor (Potentiometer): 

Allows the resistance to be adjusted manually. It's used for tuning or calibration in devices such as volume controls.

3. Thermistor: 

A resistor whose resistance changes with temperature. 

   (i) NTC (Negative Temperature Coefficient): Resistance decreases as temperature increases.

   (ii) PTC (Positive Temperature Coefficient): Resistance increases as temperature increases.

4. Light-Dependent Resistor (LDR): 

A resistor whose resistance varies based on light intensity, used in light-sensing circuits.

5. Surface-Mount Resistor (SMD Resistor): 

Small resistors designed for surface mounting on printed circuit boards (PCBs), used in modern electronic devices for space efficiency.

6. Fusible Resistor: 

Acts as both a resistor and a fuse, designed to break the circuit if too much current flows, providing overcurrent protection.

Each type of resistor is suited for different applications depending on factors like power dissipation, precision, and environmental conditions.