Overview
Civil Engineers build the body of the world; Electrical Engineers build the nervous system. They control the flow of electrons to power our cities and process our information. It is the magic behind the lightbulb and the iPhone.
Core Idea
The core idea is Controlling Electrons.
- Power: Moving lots of electrons to do work (turn a motor, light a lamp).
- Information: Moving a few electrons to send a signal (1s and 0s).
Formal Definition
The study, design, and application of equipment, devices, and systems which use electricity, electronics, and electromagnetism. Subfields: Power, Electronics, Telecommunications, Signal Processing.
Intuition
- Water Analogy:
- Voltage: Water Pressure.
- Current: Water Flow.
- Resistance: A narrow pipe.
- Electrical Engineering is plumbing for electrons.
Examples
- The Grid: The most complex machine ever built. Connecting every power plant to every outlet in the country.
- Transistor: The tiny switch that makes computers possible. A modern chip has billions of them.
- Radio: Turning sound into invisible electromagnetic waves and catching them with an antenna.
Common Misconceptions
- It’s just wiring houses: That’s an electrician. An electrical engineer designs the grid, the microchip, or the satellite.
- Electricity travels at light speed: The signal travels near light speed, but the electrons themselves move very slowly (Drift Velocity).
Related Concepts
- Ohm’s Law: $V = IR$. The fundamental equation.
- AC vs. DC: Alternating Current (Tesla/Westinghouse) for the grid. Direct Current (Edison) for batteries/electronics.
Applications
- Renewable Energy: Designing solar panels and wind turbines to feed the grid.
Criticism / Limitations
- Moore’s Law: We are shrinking transistors so much that quantum physics is starting to interfere. The “Free Lunch” of faster computers is ending.
Further Reading
- Horowitz, Paul and Hill, Winfield. The Art of Electronics.