Stephen Hawking once tried to find potential time travellers by throwing a party and only sending out invitations after the party.
17
One 75-watt bulb gives more light than three 25-watt bulbs.
57
In Arizona, a solar wind energy tower has been proposed that would generate as much energy as the Hoover Dam.
5
A ball of glass will bounce higher than a ball made of rubber.
73
The Earth's atmosphere weighs about 5.5 quadrillion tons.
108
Each day, up to 150 species of life become extinct.
-23
One gallon of used motor oil can ruin approximately one million gallons of fresh water!
71
The force of a suction cup is calculated using F=AP.
15