Iron weighs more after it rusts.
68
The force of a suction cup is calculated using F=AP.
15
The smell of freshly cut grass is actually a plant distress call.
31
In zero gravity, a candle's flame is round and blue.
16
Aluminum used to be more valuable than gold!
84
A cubic yard of air weighs about 2 pounds at sea level.
31
When you walk down a steep hill, the pressure on your knees is equal to three times your body weight.
199
The gas that gives rotten eggs their distinctive foul smell may slow ageing and block damaging chemical reactions inside cells, according to scientists in China.
5