• RiceMunk@sopuli.xyz
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    11 hours ago

    Exercise for the reader: Assuming average human eyesight, how many picoseconds away from a collision are you if you can read that size of text and the relative velocity between you and the car ahead of you is large enough that the red label is sufficiently blueshifted to look blue?

    • redsand@lemmy.dbzer0.com
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      2 hours ago

      I want to know how fast you need to go to be color shifted on a traffic camera. The more I think about it the less likely getting enough light to be picked up by the camera might be an issue even with perfect placement

    • Zkuld@lemmy.world
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      10 hours ago

      for 800nm to 400nm, we need gamma=2. So v~.86c. At 20m this gives you ~80ns.

    • glorkon@lemmy.world
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      10 hours ago

      The sticker should also say something like “But don’t worry, we’re going to be evaporated in a huge explosion anyway, due to the gigantic release of energy when you crash into my car in a few nanoseconds.”

    • spicy pancake@lemmy.zip
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      10 hours ago

      does the observer have to be able to see the sticker with normal human eyesight? if so that constrains distance (which maybe doesn’t matter?)