One cubic foot of gold weighs more than 1,200 pounds!
78
The hair of an adult man or woman can stretch 25 percent of its length without breaking.
116
Diamonds can be shattered with a hammer.
-104
It takes a photon 170,000 years to travel from the core of the Sun to the surface, but only 8 minutes to travel the rest of the way to Earth.
6
Cold water weighs more than hot water.
93
In zero gravity, a candle's flame is round and blue.
16
Optical illusions occur when what the eyes see conflicts with what the brain expects.
75
A cubic yard of air weighs about 2 pounds at sea level.
31