What is the purpose of a resistor in an electrical circuit?

The purpose of a resistor is to resist the flow of electrical current. Resistors are essential components in circuits, as they are designed to limit the amount of current that can pass through them. By doing so, they help control the voltage levels within different parts of a circuit, ensuring that components receive appropriate power levels and preventing damage.

Resistors achieve this by introducing a specific amount of resistance, measured in ohms, which converts electrical energy into heat through the process known as Joule heating. This function is crucial for protecting sensitive components, enabling proper operation of devices, and balancing circuit loads. Understanding the role of resistors is fundamental to analyzing and designing electrical circuits effectively.