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
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
Jim, you’re a fucking idiot interfering with accurate ratings and legitimate feedback. Get a hobby.
Great gift!
A little spendy, but worth it.
My wife kept talking about "ways out" being a Denver version of "psych" and she was right, so I got her this once I found it on UD. She loved it!
It's a great mug, will reccomend to family members my grandma gave me this mug for christmas and it was by far the best gift i got.
It arrived three weeks after ordering but given the holiday rush and inability of shipping to keep on schedule arrived late but was perfect little gift from me to my wife for her morning coffee with her "nickname" on the mug.
I liked the photo on your website and so I ordered the mug. You sent it right away, and it looks great!
Arrived carefully packaged
me and the boys when i get vodka mug
I ordered 3 of your mugs, with different names on them. There was a typo in the information about the name on the back of each of the mugs. This wasn’t a dealbreaker because the people who received them liked them. However, it would be nice if somebody who has basic proficiency in spelling English words could proofread the script for all of your names before they’re prepared.
Arrived on time. Great packaging. Communication with vendor was top-notch. High quality item.
I love it! Thanks! So
Great present for a retiring colleague with custom saying she's known for!
Loved this mug! So unique and you can edit the text to add something unique.
I gave it to my friend who took money from me and never returned.
I love the fact that I was able to customize my name since I've never been able to find anything with my name. The only downside is it's smaller than I thought it would be (I guess I didn't pay much attention to that), wish it was bigger, only about 10 oz total.
It's simply awesome; and plus, the word means a lot.
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