Why do veins look blue?
Science

Why do veins look blue?

A common misconception about blood is that it looks blue when depleted of oxygen, explaining why lighter-skinned people see blue veins in their arms. Here I’ll talk about how deoxygenated blood isn’t blue at all, and that the real reason for the color shows off some interesting aspects of how light interacts with matter. Special…

How do thermometers work?
Science

How do thermometers work?

Winter has come, and it’s likely that you’ll come down with a cold sometime this season. To check for a fever you’ll probably use a digital thermometer, but an old fashioned mercury and glass one will work just as well. The mercury one operates on the principle of thermal expansion, which explains many everyday physics…

Science

What causes the tides?

Previously we talked about what makes waves crash on the shore, and mentioned tidal waves as some of the largest water waves on Earth. These waves actually don’t have anything to do with the tides, though. Today I’ll tell you what makes the tides we can observe here on Earth, and mention some other cool…