Why do my eyes glow red in photos? plus 9 more videos..

Red Eye Effect - Why do my eyes glow red in photos?
Pressure - Why does popcorn pop?
Human Nose - Why does spicy food make your nose run?
Ignition Temperature - Why is it easier to burn dry leaves but not green leaves?
Thermoregulation - Why do we sweat?
Forced Vibrations - Why does a guitar have a hollow box?
Human Bones - How does a bone heal?
Human Tears - Why do onions make you cry?
Distillation - Is distilled water safe to drink?
Caffeine - How does coffee keep you awake?