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
I can pass away peacefully. This mug is everything I’ve ever needed and more. Fat thank you, Urban Dictionary. <3
I was really excited to receive this mug and when it did come it was perfect quality. My only complaint is that the color I choose was green teal but it came in yellow.
As always, easy to order and not-too-long of a wait for the finished product to arrive. It’s well-printed, and very sturdy. A great gag present for wedding party members.
The mug , color and saying are perfect! PMEO is what I say at work everyday. It has become a favorite saying for my coworkers when things go haywire!
Quality and style are outstanding relative to price point.
Love it! It is my favorite mug. Easy to hold because of its shape and weight. Now my go-to mug.
My wife is truly beautiful and this cup was perfect for her.
Awesome mugs! My GF laughed her ass off, lol!!!
t-this mug changed my life. At first i was a loner but then i bought this mug and i became HIM. I thank this mug everyday for its blessings
Cute, good quality, *****!
Exactly as expected!
My order was delivered very quickly and was high quality. Glad to add it to my mug shelf.
God is still alive. The existence of this mug shows there is still faith that god is dead and is listening to us. God Bless,
Gay Label Adore this. Ordered for my husband, with the second definition on the back, about the gay filmmaker. Makes a nice discussion starter.
Top notch shipping and exactly what I hoped!!
Best mug i have ever purchased! Subscribe
I love it, but of course the definition Ichose for “Unicorn” is too long and gets cut off after “someone is remarkably attractive.” Is there any way to purchase a second mug that has the rest of the quote on it? They’d make a great set as a present. Please let me know. David Tillinghast dtilling480@gmail.com
"Turtle on my name". A tribute to the 50 odd years of misheard lyrics.
My friend couldn’t stop laughing when I gave it to him!
I got mugged A man mugged me and then said I had da big gaye
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