Where does sweat go when the relative humidity is 100 percent? Well, there is no place for it to go—that's the point! A lesson on humidity, dew point, and heat index describes how to interpret a local weather report. A video explains the...

Rain is just water, right? Not quite! The video explains all of the other things found inside rain. It offers the science behind why rain requires these other item and how without dirt, rain would cease to exist.