What is the role of resistance in an electrical circuit?

Resistance in an electrical circuit plays a crucial role by determining how much an object impedes the flow of electric current. It is a property of materials that quantifies how much they resist the movement of electrons, which are responsible for carrying electric charge through a conductor. The higher the resistance, the less current will flow for a given voltage, according to Ohm's Law (V = IR), where V is voltage, I is current, and R is resistance.

This characteristic is fundamental to circuit design, as it allows for the control of current levels in various components, such as resistors, which are often intentionally included to manage current flow and protect sensitive components from excess current. Understanding resistance is essential when analyzing and designing circuits, as it directly impacts performance and functionality.