Optical illusions occur when what the eyes see conflicts with what the brain expects.
75
The hair of an adult man or woman can stretch 25 percent of its length without breaking.
116
Sound travels fifteen times faster through steel than through air.
134
At 15 years old, Jack Andraka invented a method of diagnosing pancreatic cancer, thus helping to save the lives of millions of people around the world. It is 168 times faster, 26,000 times cheaper, 400 times more sensitive, and has a 99% success rate.
15
A cesium atom in an atomic clock beats over nine billion times a second.
43
German chemists made a replica of a trophy the size of one molecule.
68
The smell of freshly cut grass is actually a plant distress call.
31