Lesson 4 – V: Voyage into Volt: How Do I Build a Circuit and Calculate Power & Energy?

Pick up any small device you use every day — a phone charger, an LED lamp, a small fan. It feels simple to plug in and turn on. But an engineer designing a system to power it has to answer a harder question first: how much electricity does this actually use, and how would you figure that out before building anything?

In the last lesson, you measured voltage and current. In this lesson, you will build your own circuit, add resistance to the picture, and use a single relationship — Ohm’s Law — to design a circuit toward a goal. Then you will turn your measurements into power and energy, the numbers engineers actually use to make decisions.