Electricity Basics: Charge, Voltage and Current
Everything electronic - your phone, an LED, a robot motor - runs on three simple ideas: charge, current and voltage. Master these three words and the rest of electronics becomes easy. This is lesson 1 of 12, and it is the foundation for everything that follows.
What you will be able to do after this lesson
- Explain what electric charge is and which tiny particle carries it.
- Say exactly what current means and read a current value in amperes (A).
- Explain voltage using the water-tower picture and read a voltage in volts (V).
- Understand why we draw current one way even though electrons move the other way.
- Describe a complete circuit and tell an open circuit from a closed one.
- Tell the difference between conductors and insulators, and why a short circuit is dangerous.
- Know the basic safety rule: low voltage is safe to handle, mains voltage can kill.
The big idea in one sentence
Electricity is tiny charged particles (electrons) moving through a material, pushed along by electrical pressure.
That is really all it is. The "tiny charged particles" give us charge. Their movement is current. The push that makes them move is voltage. Everything else in this course is built on those three words, so we will take them one at a time and very slowly.