Uploaded May 2019 | Updated September 2026, 3 weeks ago

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When physics students first learn about Newton's law and momentum, they get the impression that it's all about mass. If that's true, how can mass-less light have momentum? It's because mass isn't actually required.
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VIDEO ANNOTATIONS/CARDS

What the HECK is Energy?
youtu.be/snj1wBtn6I8

What the HECK is Mass?
youtu.be/XkPudRiWspc

Circuit Energy Flow:
youtu.be/C7tQJ42nGno

How Does The Crookes Radiometer Work?
youtu.be/Li_nmKw4Buc
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RELATED YOUTUBE VIDEOS

Crash Course Physics:
youtu.be/kKKM8Y-u7ds
youtu.be/Y-QOfc2XqOk
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OTHER SOURCES

http://hyperphysics.phy-astr.gsu.edu/hbase/Newt.html
http://hyperphysics.phy-astr.gsu.edu/hbase/impulse.html
http://www.feynmanlectures.caltech.edu/II_27.html
en.wiktionary.org/wiki/peto#Latin
physicsclassroom.com/class/newtlaws/Lesson-2/Types-of-Forces
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LINKS TO COMMENTS

Momentum and Mass:
youtube.com/watch?v=73XdlgzSKws&lc=UgyD-5npaPrpv-oncWF4AaABAg
youtube.com/watch?v=ueuwWiR-Dw4&lc=Ugx999c0Yp1AxyQe-NB4AaABAg
youtube.com/watch?v=ueuwWiR-Dw4&lc=UgyplNXqLIrgIpDJqR94AaABAg
youtube.com/watch?v=ueuwWiR-Dw4&lc=UgzbI1ccsf1oSUpXK014AaABAg
youtube.com/watch?v=ueuwWiR-Dw4&lc=UgzGnc5tQg4olvPiPXF4AaABAg

Light through Coil:
youtube.com/watch?v=3TufSRaHB6g&lc=UgyJDwtKdgihPhBz6D14AaABAg
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IMAGE CREDITS

Solar Sail:
nasa.gov/connect/chat/nanosail_chat.html