Photoresistors are light-dependent resistors whose resistance changes depending on the amount of light hitting the sensor. This makes them perfect for light-controlled switches and projects. When paired with a relay (which we’ll cover in a later lesson) they can be used to turn on a light bulb when it gets dark, track daylight in a weather station, and much more. Similar to photoresistors, thermistors change resistance depending on the temperature. You can build projects that perform an action like lighting an LED or sounding an alarm when the temperature goes above a certain point or even turn on other components like fans and motors. They’re ideal for equipment control and protection circuits.
MATERIALS:
You’ll be able to follow along and build all the projects featured in this course with the ELEGOO UNO Project Super Starter Kit.
LESSON CONTENT:
- How photoresistors work
- Using photoresistors in your circuits
- Build an LED night light that turns on when it’s dark
- Make a buzzer that changes tone according to the brightness of light
- How thermistors work and temperature coefficients
- Using thermistors in your circuits
- Converting resistance to temperature readings using the Steinhart-Hart equation
- Build an LED and sound warning system when the temperature goes above a certain number
- Assignment
LESSON 7: Servos