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 Tee
The Fucklix t shirt is perfect but I am still waiting for the xlarge I ordered. These are gifts and will be just what is needed. Hope I receive the xlarge soon then it's time to give them to the people I ordered them for. So glad I saw them . Thanks.
My wife loves it. Nice quality and so funny for the wearer. Thank you!
The shirt fit amazing, package was shipped rather fast! Thank you so much..
It is absolutely perfect and I love wearing it. Thank You.
Love the short mine says bih on it
this shit stays on during sex
Love it! Buyed it for my sister but I had to make it say her favorite anime 💀✨
LOVR THIS SHIRT OML SO CUTEEEEE😍😍😍
mine had gay on it. Instant sex.
I love my NIckIsBum T-Shirt, it is very comfortable.
used it as a cum rag
Great fit and soft material. Gave as gift. Big hit!
Great conversation piece! Plus I can never find anything with my name on it. This was a great find! Will definitely order more!!!!
Got exactly what I wanted.
Exactly what I expected, thanks!
I don't visit Urban Dictionary alit so I only recently saw they offered merch. I immediately started looking up words for potential Christmas gifts. Found the ideal gift for my brother & ordered a shirt. It arrived very quickly and I love it. It's exactly as pictured on the site and being able to customize it with his name makes it perfect. I only hope he loves it as much as I do. Will definitely keep Urban Dictionary in mind when I need to find a great gift.
i love my shirt i made it say sapnap cause yassssssssss
Best This is the best shirt I have ever gotten I love it and I definitly recomend it to any friend named Hailie
So cool to quickly be able to turn a trending phrase into wearable art!
it was really good i put dad with the def of tfu and lol
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Size Guide
Measurements may vary by up to 2" (5 cm). Pro tip: Measure one of your t-shirts at home and compare!
A - Length
Measure from the top of the collar to the bottom hem
B - Width
Measure across the chest from armpit to armpit
Size Chart
| Size | Length | Width |
|---|---|---|
| XS | 27" | 16½" |
| S | 28" | 18" |
| M | 29" | 20" |
| L | 30" | 22" |
| XL | 31" | 24" |
| 2XL | 32" | 26" |
| 3XL | 33" | 28" |
| Size | Length | Width |
|---|---|---|
| XS | 69 cm | 42 cm |
| S | 71 cm | 46 cm |
| M | 74 cm | 51 cm |
| L | 76 cm | 56 cm |
| XL | 79 cm | 61 cm |
| 2XL | 81 cm | 66 cm |
| 3XL | 84 cm | 71 cm |