A cubic yard of air weighs about 2 pounds at sea level.
31
A ball of glass will bounce higher than a ball made of rubber.
73
When you walk down a steep hill, the pressure on your knees is equal to three times your body weight.
199
Diamonds can be shattered with a hammer.
-104
The bark of an older redwood tree is fireproof.
65
If the chemical sodium is dropped into water it will immediately and violently explode.
67
Liquid TIDE laundry detergent glows under a blacklight.
96