One thing I love about sharing NICERC content with teachers all over the country is the number of rich, educational opportunities the curriculum provides. In STEM EDA, students learn the basics of electricity, how a battery works, and what constitutes a complete circuit. In Cyber Literacy, as students begin to explore circuits and robotics, they discover the direction in which electrical current flows…or so we say.
Going as far back as the 1700’s, scientists and hobbyists dabbling in the growing field of electricity understood electricity as flowing like a fluid of sorts. It was even referred to as “electric fluid”. This mysterious flow of electricity only occurred when a circuit was completed – but which way was the current flowing? Many experiments were undertaken in the late 1800’s without any convincingly definitive findings. Finally, in order to establish a basis for further understanding, American founding father Benjamin Franklin, an amateur scientist in his own right, decided to proclaim that electricity flows from positive to negative. Today, we refer to Franklin’s decision as “conventional flow”. Surprisingly, this is how electrical engineers, electricians, makers, builders, and others think of electricity – by conventional flow. All the technology of today built to harness electrical power: cell phones, computers, satellites, electric cars, drones, and more – they were all designed using Franklin’s concept of conventional flow!
It wasn’t until electrical experimentation had become sufficiently advanced were we able to discover that Franklin’s “conventional flow” is actually backwards! That’s right – electrons and electrical energy transfer actual flows from negative to positive. The understanding that electrons flow from negative to positive is referred to as “electron flow” – which is opposite of “conventional flow”. In spite of Franklin having guessed wrong and an entire thriving electronics industry growing to the point where it is today, engineers and designers still plan, think about, and build circuits with a “backwards” mentality. The idea that anything works at all is, to me, perhaps one of the more amazing things about society when you stop to think about it.