Obeying the law (of physics)! Kinetic energy and momentum explained @AppliedScience

Uploaded December 2014 | Updated September 2026, 2 weeks ago

In my video on the Crookes Radiometer, I showed that the devices spin because of a thermal gas effect -- not the force of photons hitting the vanes. In the comments section, someone asked about kinetic energy and how incoming photons impart force to the rotor. This video is a more complete answer to that question.

Obeying the law (of physics)! Kinetic energy and momentum explained

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$Holograms on chocolate DIY process to copy commercial holograms onto chocolate! Completely edible no dyes or inks used. Tech Ingredients video: https://www.youtube.com/watch?v=SoTi0tM4yQ8 Samy Kamkars diffractive chocolate: https://twitter.com/samykamkar/status/1259173832620830722 Hologram stickers: https://www.ebay.com/itm/100-Huge-1-9-16-Round-Adhesive-Hologram-Sticker-Labels/331178956157 Silver mirror process: https://sci-hub.tw/https://doi.org/10.1080/00202967.1941.11869396 Add a pinch of sodium lauryl sulfate to the stannous chloride primer solution to help the solution get into contact with the plastic surface. https://www.youtube.com/watch?v=y-4qqcCxD6g Morphotonix: https://www.npr.org/sections/thesalt/2014/06/14/321816570/holographic-chocolates-look-as-beautiful-as-they-taste http://www.morphotonix.com/products/ Caswell nickel electroplating kit: https://www.caswellplating.com/electroplating-anodizing/nickel-plating-kits/nickel-electroplating-kit-1-5-gal.html (Price was already pretty high years ago, and has gone up a lot since; and the kit has fewer components than it used to. But it does work well.) Holography Marketplace book lots of very practical information for making your own holograms, and good source of suppliers (though many are out-of-business now): https://www.amazon.com/Holography-MarketPlace-6th-Franz-Ross/dp/0894960997 Very good source for mold making supplies: https://shop.smooth-on.com/ Countermeasures against hologram copying. Holograms are often used as a security seal, so making copies as shown in the video could be a problem without countermeasures: http://www.nli-ltd.com/publications/countermeasures.php I was planning to talk more about different types of holograms in technical detail, but I think I will save it for a future, dedicated video on making original holograms. https://www.patreon.com/AppliedScience$

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Obeying the law (of physics)! Kinetic energy and momentum explained