When you walk down a steep hill, the pressure on your knees is equal to three times your body weight.
199
Iron weighs more after it rusts.
68
One barrel of petroleum holds 42 gallons.
20
Termites are being researched as a possible renewable energy source as they can produce up to 2 litres of hydrogen from ingesting a single sheet of paper, making them one of the planet’s most efficient bioreactors.
24
If the chemical sodium is dropped into water it will immediately and violently explode.
67
Indoor pollution is 10 times more toxic than outdoor pollution.
62
The hair of an adult man or woman can stretch 25 percent of its length without breaking.
116
Nearly 50% of the world's scientists are assigned to military projects.
71