Unit 9: Light


Energy can take one of two forms: matter and light (called electromagnetic radiation). Light is energy in the form of either a particle or a wave that can travel through space and some kinds of matter, like glass. We’re going to investigate the wild world of the photon that has baffled scientists for over a century.


Low electromagnetic radiation (called radio waves) can have wavelengths longer than a football field, while high energy gamma rays can destroy living tissue. We’re going to have a look at the nutty fellow called the ‘photon’ and its very odd behavior during two important experiments that, at first glance, seem to be in conflict with each other. The behavior of light is so strange that scientists are still trying to work out the details.


NOTE: We’re fixing the navigation, so you will notice changes to the menu on the right while we spiff up the website!



One of the best things you can do with this unit is to take notes in a journal as you go. Snap photos of yourself doing the actual experiment and paste them in alongside your drawing of your experimental setup. This is the same way scientists document their own findings, and it’s a lot of fun to look back at the splattered pages later on and see how far you’ve come. I always jot down my questions that didn’t get answered with the experiment across the top of the page so I can research it more later. Are you ready to get started?


Unit 9: Light & Lasers Teleclass

This is a recording of a live teleclass I did when this unit was first released. This is a great way to get introduced to the unit you’re about to do and get started. I’ve included it here so you can participate and learn, too! To listen to the audio recording, download the teleclass mp3 here.


Unit 9: Getting Started with the Lessons

Get started with Lesson 1: Light Waves!