Homeschool Electronics 101 - What is voltage?

EEME makes monthly hands-on project kits and online lessons to teach kids electronics.

Due to COVID-19, my 3rd grade son continues to do distance learning. I have been sharing what I've learned as a newbie home-edu facilitator, such as having my son manage his workload by using a timer, playing mad-lib to improve his writing, coaching him on being confident to say "I don't know", among others I've been publishing on this EEME blog.


Fanning our kid's sparked interests

My kids learn more effectively when I, as a parent, understand some of the basics of what they are looking to learn. For instance, my son has recently grown an interest in battleships. So I researched a bit about World War 2 battleships and trickled fun facts to him which helped further progress his interest beyond battleships and into WW2 history.

For parents with kids who have strong interests in electronics (or colloquially referred to as "electricity"), researching about "electricity" can be extremely daunting. A web search immediately results in scary equations and descriptions ladden with nomenclature.

So I decided to dedicate a couple of posts to talk about the basics of "electricity" in the most intuitive and friendly manner possible.

This way, during dinner, you can impress your kids (and spouse) with the new found knowledge!!


What is voltage?

There are 3 main elements of "electricity" - voltage, current, and resistance. The most common element would arguably be voltage. You see it on batteries. Some of you may know 120 volts are supplied through our United States wall outlets.

You often hear that high voltage can kill you, which is not the complete story. It's high voltage combined with high electric current (which we'll talk about in a follow-on post) that can kill you, not just high voltage. You get zapped with high voltage every day. It's called static. Static main be painful, but it is not fatal. So next time you see a "high voltage" warning sign, know that it should actually read "high voltage + high current".

What is voltage? People sometimes refers to voltage as "power" - ie how much power does that battery have, 3 volts, 9 volts? Voltage contributes to power but on it's own, voltage is more accurately represented as "pressure".

Five Whys

Intuitively speaking, voltage is the pressure to push electrons through a medium such as wire. The higher the voltage, the more pressure there is to push the electrons through.

This "pressure" interplays with the other 2 elements - current and resistance - to power our fridge, light up our lightbulbs, run our smartphones. Without enough voltage, there wouldn't be enough "pressure" to push the electrons through a lightbulb filament to light it up.


What is ground?

When talking about voltage, it is inevitable to also hear the word "ground". Ground is often thought of as where voltage is zero. But that is also not the complete picture.

To intuitively understand "electric ground", let's think a bit about a physical ground. If you hold a ball 5 feet above the ground, you can say the ball is at an elevation of 5 feet. But that's relative to the ground you are standing on. What if your ground was in Denver Colorado, about 5000 feet above sea level? To someone standing at sea level in New York City, the ball is actually 5005 feet above their ground.

Five Whys

Voltage and "electric ground" acts similarly. Similar to height/elevation, voltage "pressure" is always relative to some "ground" voltage. For example, you often stack 2 AA batteries together in an electronic device. Each AA battery is 1.5 volts - relative to each battery's individual ground (ie bottom of that specific battery).

Stacked together, 2 AA batteries can provide 3 volts but only relative to the ground of the bottom battery. If you measure the voltage relative to the ground of each individual battery, even though the batteries are stacked, the "electric pressure" is still only 1.5 volts for each individual battery. The positive end of the top battery is the ball held up in Denver and the ground negative end of the bottom battery is the ground at New York City.


Conclusion

Hopefully now you have an intuition of what voltage (and ground) is. Go tell your kids what you learned during dinner and have them ask you questions you cannot answer!

I welcome you to post those "hard" questions back to me - via email dad AT eeme DOT co, via our EEME Facebook page, or @projecteeme Instagram page. I look forward to answering them, help contribute to your family's adventures in learning electronics.


If you are looking for hands-on electronics kits for your 7-12 year old kid, we are still shipping during this COVID-19 fiasco. Each kit is paired with its own online curriculum to teach your family how to build the circuit as well as how the circuit works.

You can learn with EEME in three ways:

  1. Sign up for FREE, to learn with our free online lessons

  2. Subscribe to our monthly kits - each month we send you a new project.

  3. Make a one-time purchase of our 9 project set - which is effectively the first 9 month's of projects.

Thanks so much, stay safe, and happy building!!
Jack "EEME Dad"


PS - EEME's a small shop with a tiny marketing budget. So please help us spread the word by sharing EEME with others. Thx!