In this episode we use near infrared (near-IR) light to look at and through different objects. Near-IR is a kind of light we can’t see that is just beyond the red end of the rainbow. Some things that are opaque to visible light are transparent to infrared, including plastic bags and your skin! However, the blood in your veins absorbs near-IR light and appears dark.
Waves are one way in which energy can be sent down a string. When two waves meet, they interact.
Liquid oxygen is collected on a pretzel, and when lit it burns like a Roman Candle!