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Fun-Fact thread






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Fun-fact: Blu-ray lasers are not actually blue - they are violet.

Fun-fact: Female kangaroos have three vaginas.

Fun-fact: Women love diamonds for the wide range of industrial applications.
 
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Fun-fact: Women love diamonds for the wide range of industrial applications.

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Fin fact: Population smaller than that of New York City.
 
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When people go in for eye cancer treatment, they sometimes get something called "linac photon treatment." It's a linear accelerator that makes a beam of electrons, which slams into a block of tungsten. That produces gamma rays through bremsstrahlung. In medicine the term "gamma ray" is reserved for photons that come from the nuclear decay, while anything produced by machine is called x-rays. However, these photons are so energetic (4-25 MeV) that they just call them "high-energy photons." The most energetic photons that come out of a nuclear explosion are only 10 MeV, so 25 MeV is basically astronomy-grade.

The beams are pulsed, megawatts if you just measure the pulses, kilowatts if you average it out over a second. People who get these treatments see flashes of light, 90% of the time blue, 10% of the time white. The blue flashes are Cerenkov radiation generated in or near the retina while the white flashes are direct stimulation of the rods or cones.
 
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Fun fact:

The state of Washington is the only state to be named after a United States president.

George is a city in Grant County, Washington, United States. The population was 501 at the 2010 census. It takes its name from George Washington, and is the only town in the United States to bear the full name of a US President.

Alan
 
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Fun Fact: Previous fun fact accounted for inflation.

You've been watching faux news too much if you think taxes are the sole (or even the main) contributor of inflation.

All else equal, US revenue increases because GDP increases. Tax rates are currently at low values, historically.
 
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You've been watching faux news too much if you think taxes are the sole (or even the main) contributor of inflation.

Of course not.

Fun Fact: Best to rely on facts to prove your point, and not crappy puns.

Fun Fact 2: The words spoken by the character Groot, in the Guardians of the Galaxy film, were recorded by the voice actor in multiple languages.
 
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Most microwave ovens do not actually have a variable power level, they simply cycle on and off power to the Magnetron tube at a very low frequency using a relay. Typical oscillation cycles are 6 seconds long. At 50% power the magnetron is switched on for six seconds, and then off for six seconds. The result is that low power settings and short cook times are inaccurate. Setting the oven on for 12sec at half power is the same as 6sec at full power. Microwaves featuring "inverter" technology actually use a PWM function on the high frequency drive to achieve near linear output power variability.

Related: contrary to popular belief, microwaves do not actually cook from the inside towards the outside of the food. Microwaves cook identically to any other electromagnetic energy deposition system (infrared heating, i.e. next to a flame or in a broiler); from the outside in, relying on conduction of heat from the outer layers to the internal layers. The drying effect microwaves have on food is directly related to how much slower heat is transferred towards the center of the food than heat is being deposited into the outer layers. The idea temperature is exceeded externally while not being achieved internally. The solution is to use a longer cook time at an (actually) lower power level, to give conduction more time to work.
 
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^ I figured that was obvious since you can hear it turning on and off.

Fun fact: The laser mouse not working on a diffraction grating is not 100% true. Mine works on one.
 
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Glass takes one million years to decompose,
which means it never wears out and can be
recycled an infinite amount of times!


The roar that we hear when we place a seashell next to our ear is not the ocean, but rather the sound of blood surging through the veins in the ear.

Nine out of every 10 living things live in the ocean.

The Swine Flu vaccine in 1976 caused more death and illness than the disease it was intended to prevent.

The military salute is a motion that evolved from medieval times, when knights in armor raised their visors to reveal their identity.

When a person dies, hearing is the last sense to go.
The first sense lost is sight.

Due to earth's gravity it is impossible for mountains to be higher than 15,000 meters.

The moon moves about two inches away from the Earth
each year.
 
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The military salute is a motion that evolved from medieval times, when knights in armor raised their visors to reveal their identity.

Cool, didn't know that.

In feudal Japan, the importance of skill with swordfighting wasn't nearly as prevalent as modern culture makes it out to be.

The most important skill was archery with Japanese longbows. One claiming he was deadly swordfighter was basically admitting that he sucked with longbow, which was the primary battlefield weapon of the era, since it far outreached the sword, which was used as a backup weapon only.
 
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The galactic year, also known as a cosmic year, is the duration of time required for the Solar System to orbit once around the center of the Milky Way Galaxy, is somewhere between 225 to 250 million terrestrial years.

An object traveling at the speed of light could circumnavigate the Earth's equator in 2 minutes and 54 seconds -and- 1 inch is 2.54 centimeters. Hmmmm...
 




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