Airports that are at higher altitudes require a longer airstrip due to lower air density.
39
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
There are more atoms in one teaspoon of water than there are teaspoons of water in the Atlantic Ocean.
13
Cellophane is not made of plastic. It is made from a plant fiber, cellulose, which has been shredded and aged.
44
Cold water weighs more than hot water.
93
Because heat expands the metal, the Eiffel Tower always leans away from the sun.
79
One gallon of used motor oil can ruin approximately one million gallons of fresh water!
71
Balsa wood is classified as a hard wood!
41