2.1 Voltage: The Driving Force

Introduction to voltage: Voltage is a fundamental concept in electricity that represents the electric potential difference between two points in a circuit. It is often referred to as the "driving force" behind the flow of electric current. Voltage is measured in volts (V) and is denoted by the symbol "V".

Voltage measurement: Voltage can be measured using a device called a voltmeter. A voltmeter is connected across the two points between which the voltage is to be measured. It provides a numerical value that indicates the potential difference between those points.

Voltage sources: Voltage in a circuit is typically provided by voltage sources. These can be batteries, generators, or power supplies. A voltage source establishes a potential difference between its two terminals, creating an electric field that drives the flow of electrons in a circuit.

Voltage drop: When a current flows through a circuit, there may be a decrease in voltage across certain components such as resistors, capacitors, or inductors. This decrease is known as a voltage drop. Voltage drops are essential to understanding the distribution of voltage within a circuit.

Voltage in series and parallel circuits: In a series circuit, the total voltage is divided among the components connected in series. Each component experiences a portion of the total voltage, and the sum of the voltage drops across all components equals the total voltage. In contrast, in a parallel circuit, the voltage across each component is the same. The total voltage is maintained across all parallel branches.

By understanding voltage and its characteristics, we gain a deeper insight into the behavior of electric circuits and how voltage influences the flow of current.