Gizmodo University: Volts, Amps, and Ohms


In this week's Gizmodo University: Discover Electronics, we're diving headfirst into the principle theories of electronics. The second of four classes in this series, "Volts, Amps, and Ohms" is presented in conjunction with Sparkle Labs.

Good morning class, today we will be building off of last week's introduction to electronics theory. If you missed last class, please take a moment and review the last lesson, paying special attention to Chapter 5. Right then, let's get started.

Chapter 1: The Resistor

The Resistor from Sparkle Labs on Vimeo.

So, now that we've got the basics of resistance down and can recite that handy mnemonic from memory (Big Boys Race Our Young Girls But Violet the Great Wins). we'll move onto Dividing Voltage. If you think you've got a better mnemonic, tell us in Comments!

Chapter 2: Voltage Divider

Voltage Divider from Sparkle Labs on Vimeo.

Take some time to experiment with your new voltage divider and familiarize yourself thoroughly with it because we're taking this concept a step further with our discussion of circuits in series and parallel.

Chapter 3: Series / Parallel

Series and Parallel from Sparkle Labs on Vimeo.

Remember, two resistors in series will increase the resistance by R = R1+R2, two resistors in parallel will decrease resistance by 1/R = 1/R1 + 1/R2. If you are having trouble understanding the math or concepts, feel free to ask your Sparkle Labs TA in the Comments section below!

Chapter 4: Ohm's Law

Ohm's Law from Sparkle Labs on Vimeo.

Simply put: voltage goes up, current goes up; resistance goes up, current goes down. This is the basis of Ohm's Law: Voltage = Current x Resistance (V=IR). Once you've gotten the hang of it, see if you can replicate the calculation from the video. Up next, using Ohm's Law to pick the right resistor for the job.

Chapter 5: Determine the Correct Resistor

Det ermine resistor for your LED from Sparkle Labs on Vimeo.

Now I know what you're thinking, "Why didn't he tell us about Wolfram Alpha to begin with? Why all the math on a Saturday morning?" Because math builds character, that's why.

Thanks, that's it for this week. If you've got any additional questions, TA's are waiting and eager to help in the Comments section until 2pm Eastern. Check out Sparkle Labs for more information. We'll see you back here, next Saturday, at 12pm Eastern for Lesson 3: Sensors and Transistors.