Lesson 17:

Electrical Devices

and Circuits

If you've ever sat watching a thunderstorm, with mighty lightning bolts darting down from the sky, you'll have some idea of the power of electricity. A bolt of lightning is a sudden, massive surge of electricity between the sky and the ground beneath. The energy in a single lightning bolt is enough to light 100 powerful lamps for a whole day or to make a couple of hundred thousand slices of toast!

Electricity is the most versatile energy source that we have; it is also one of the newest — homes and businesses have been using it for not much more than a hundred years. In this lesson, you will take a closer look at electrical devices and circuits and find out how they work!