radiometer
A radiometer or roentgenometer is a device for measuring the radiant flux (power) of electromagnetic radiation. Generally, a radiometer is an infrared radiation detector or an ultraviolet detector.1 Microwave radiometers operate in the microwave wavelengths. While the term radiometer can refer to any device that measures electromagnetic radiation (e.g. light), the term is often used to refer specifically to a Crookes radiometer ("light-mill"), a device invented in 1873 in which a rotor (having vanes which are dark on one side, and light on the other) in a partial vacuum spins when exposed to light. A common belief (one originally held even by Crookes) is that the momentum of the absorbed light on the black faces makes the radiometer operate. If this were true, however, the radiometer would spin away from the non-black faces, since the photons bouncing off those faces impart more momentum than the photons absorbed on the black faces. Photons do exert radiation pressure on the faces, but those forces are dwarfed by other effects. The currently accepted explanation depends on having just the right degree of vacuum, and relates to the transfer of heat rather than the direct effect of photons. 23 A Nichols radiometer demonstrates photon pressure. It is much more sensitive than the Crookes radiometer and it operates in a complete vacuum, whereas operation of the Crookes radiometer requires an imperfect vacuum.
The Urban Dictionary Mug
Cute, simple, as advertised.
My great great great great great uncle’s dog’s daughter’s owner’s sister loved this mug. Must recomend!!!
Got this for my dog
As a Jolology major, I love my new mug!
It was for a friends 70th b-day. When we order it, it was going to come 2 day after the party. But we were so excited it came 3 days before his party. It was a big hit. Thank you.
I gave it as a gift and the recipient loved it. No indication where it was made, so maybe USA? That would be really nice, if so.
I appreciated the email asking if the content was correct. Excellent quality and attention to detail. Thank you!
its an incredible mug! i would recommend purchasing this awesome product!
Damonism and #Stolen Valor Coffee Mug These coffee mugs are rugged, solid, high quality and keep the liquids hotter, longer. The definitions of both mugs are spot-on! I will definitely by more. Great work Urban Dictionary!
why is this a real thing? AND YA'LL ACTING LIKE IT'S NORMAL!?
I really like the mug, but I thought I had ordered the all pink one. What came was a white with a block of pink with "Fubar" written on it.
the only reason why i care about humanity this mug is the reason why i believe humanity deserves a second chance, even after they blaspheme my name. this mug is the greatest thing i've ever seen and i have ordered many of them. this mug replaces the holy grail. the bible should've told about the wonderful deeds of the mug and how it saved humanity from my wrath. alas, whilst the laws keep me from tampering with human minds and altering holy objects like the bible, i can only pass on my message: "spread the news and buy this mug!"
Its.. omg, its............. AMAZING AMAZING OMG ITS SOOO GOOD
A mug for your boyfriend Paul????? My boyfriend is not called Paul. I don't even have a boyfriend
Great mug... finally got my ""your mom gay lol" mug, I'm so happy
ariana grande mug omg this slays mah life
It was easy to correct grammar when necessary, and then to order a great gift for a member of a wedding party. Nice, simple, and sturdy mug.
with this we regain gods trust This mug changes my views of humanity. I think we may have a chance of not going extinct. Everyone should own this fantastic mug. Oh it's also has a nice handle.
Love that I got an Urban Dictionary word definition from someone I know! So much fun and great memory item!! 😊
I like it but it took a long time getting here
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