Voltage, Current, and Resistance

Voltage, Current, and Resistance

What is Voltage?

Voltage (V) is the electrical pressure that pushes current through a circuit. It's measured in Volts (V).

Think of voltage like water pressure in a pipe - the higher the pressure, the more water flows.

What is Current?

Current (I) is the flow of electrons through a conductor. It's measured in Amperes (A).

# Water analogy

Voltage = water pressure

Current = water flow rate

What is Resistance?

Resistance (R) opposes the flow of current. It's measured in Ohms (Ω).

Higher resistance = less current flow (like a narrow pipe).

Key Units

QuantitySymbolUnitSymbol
VoltageVVoltV
CurrentIAmpereA
ResistanceROhmΩ

Electronic Components Overview

Before we dive deeper, let's familiarize ourselves with common electronic component symbols:

Electronic schematic symbols Common electronic component symbols used in schematics

Summary

  • Voltage - electrical pressure, measured in Volts
  • Current - electron flow, measured in Amps
  • Resistance - opposition to flow, measured in Ohms

Next Lesson

In the next lesson, you'll learn about Ohm's Law - the fundamental relationship between voltage, current, and resistance.

Quiz - Quiz - Voltage, Current, and Resistance

1. In which units do we measure voltage?

2. What is electric current?

3. What does resistance measure?