Airports that are at higher altitudes require a longer airstrip due to lower air density.
39
In zero gravity, a candle's flame is round and blue.
16
No matter how cold it gets, gasoline will not freeze.
107
A cesium atom in an atomic clock beats over nine billion times a second.
43
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
Scientists concluded that the chicken came first, not the egg, because the protein which makes the egg shells is only produced by hens.
11