When you walk down a steep hill, the pressure on your knees is equal to three times your body weight.
199
Brass doorknobs automatically disinfect themselves in about 8 hours.
18
Optical illusions occur when what the eyes see conflicts with what the brain expects.
75
The Earth's atmosphere weighs about 5.5 quadrillion tons.
108
Oak trees produce 2,200 acorns in a season, but each acorn only has a 1 in 10,000 chance of becoming an oak tree.
304
Some toothpastes and deodorants contain the same chemicals found in antifreeze.
38
Stannous fluoride, which is the cavity fighter found in toothpaste is made from recycled tin.
65
Most liquid laundry detergents are alive with living organisms that help to break down stains!
88