Chapter 3. How to build circuits
This chapter covers
- Using Ohm’s law to manipulate voltage, current, and resistance in a circuit
- Prototyping basic circuits on breadboards
- The difference between parallel and series circuits
- Nitty-gritty details about LEDs and how to wire them up in several useful configurations
- Identifying and selecting the right resistor for different circuits and components
- Calculating the resistance in a series circuit and a parallel circuit

For this chapter, you’ll need
- 1 Arduino Uno
- 4 standard LEDs, red
- 4 220 V resistors
- 4 560 V resistors
- 1 100 V resistor
- 1 push-button switch
- 1 9 V battery
- 1 9 V battery snap ...