When you walk down a steep hill, the pressure on your knees is equal to three times your body weight.
199
Airports that are at higher altitudes require a longer airstrip due to lower air density.
39
Iron weighs more after it rusts.
16
Approximately 70 percent of the earth is covered by water. Only 1 percent of this water is drinkable.
65
The left ear is more responsive to words of love and emotion whispered into it than the right.
40
Columbia University has developed an artificial tree that passively soaks up carbon dioxide from the air using "leaves" that are 1,000 times more efficient than true leaves that use photosynthesis.
15
Scientists aren't sure what color dinosaurs were.
312