Because heat expands the metal, the Eiffel Tower always leans away from the sun.
79
For every gallon of sea water, you get more than a quarter pound of salt.
45
When you walk down a steep hill, the pressure on your knees is equal to three times your body weight.
199
MIT has developed a camera that captures the speed of light at a trillion frames per second.
20
In Arizona, a solar wind energy tower has been proposed that would generate as much energy as the Hoover Dam.
5
Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
Sound travels about 4 times faster in water than in air.
408
0.3% of solar energy from the Sahara is enough to power the whole of Europe.
310