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
Cole M. gifted one for me on my birthday. I will never forget that day. 10/10
I didn’t get one yet but if I did it would also be for Cole M.’s girlfriend, we would have amazing sex
Was a gift and arrived on time. Just as advertised. Lots of fun.
The price is a little bit expensive, but the gift arrived as ordered. Thanks!
The price was a little expensive, but the gift arrived as ordered. Thanks!
Great mug got one for my highschool crush
I was very pleased with the mug and I was thrilled that I could purchase a customized item that perfectly suited the person I was gifting. The only issue I had was that it didn't have the quote from the tv show the word came from as that was pictured on the mug prior to purchase.
Came out just as described! Had the full definition. Very pleased!
Perfect gift As a joke I gave one to my mate but I costumised it. It said tom drunk 24/7 ugly and got lovely hair. The lovely hair part was a joke coz he don’t have any. It was his favourite gift he got for his birthday and he drinks his beer out of it 😂
Great mug…. Got one for Cole M.’s girlfriend.
I ordered a customized mug for my gf and everything came out well. There were no autocorrect mistakes and the mug was unscratched. Would shop here again
Also got one for Cole M.'s girlfriend, even faster sex.
Istgd imma force my mum to buy this idek hw i find out but this shit looks fucking fire
Perfect coffee cup for a hockey fan. Great conversation starter.
Perfect gift! My husband loved it. So funny and clever!
Great mug… got one for my girlfriend… instant sex
As always, these are well made mugs that stand up to most anything. And they make perfect gifts (in this case for dirty-minded members of a wedding party). I’m extremely pleased.
Is a great mug that I purchased as a gag gift for a coworker. You know the one who also as interesting words/phrases that only urban dictionary can explain. Great as a coffee mug and better as conversation piece!
👍
The mug exceeded my expectations. Really excellent quality and build
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