# \#laser

**URL:** https://scanalyst.fourmilab.ch/tag/laser/3492.md

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## [Build Your Own 500 Watt Computer Target Tracking Laser Weapon](https://scanalyst.fourmilab.ch/t/build-your-own-500-watt-computer-target-tracking-laser-weapon/4166)

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**Author:** [@johnwalker](https://scanalyst.fourmilab.ch/u/johnwalker)\
**Replies:** 4\
**Last updated:** [3 January 2024 15:11 UTC](https://scanalyst.fourmilab.ch/t/build-your-own-500-watt-computer-target-tracking-laser-weapon/4166 "2024-01-03T15:11:35Z")

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What could possibly go wrong?

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## [Mystery Illuminating a Crookes Radiometer with an Infrared Laser](https://scanalyst.fourmilab.ch/t/mystery-illuminating-a-crookes-radiometer-with-an-infrared-laser/2517)

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**Author:** [@johnwalker](https://scanalyst.fourmilab.ch/u/johnwalker)\
**Replies:** 0\
**Last updated:** [28 December 2022 13:48 UTC](https://scanalyst.fourmilab.ch/t/mystery-illuminating-a-crookes-radiometer-with-an-infrared-laser/2517 "2022-12-28T13:48:31Z")

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When you shine an infrared laser on the vanes (particularly the black side) of a Crookes radiometer, the invisible beam makes a bright white spot where it strikes the vane. Quantum mechanics forbids photon…