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Cake day: June 15th, 2023

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  • hinterlufer@lemmy.worldtoScience Memes@mander.xyzkawaiiiiiii
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    23 days ago

    So, a typical pupil is around 2 mm in diameter in bright conditions. With the Rayleigh limit that results in an angular resolution of 1.22 * 60010^-9 m / 210^-3 m = 3.66*10^-4 rad

    At a distance of 5 x 3 mi = 15 mi = 24.1 km this corresponds to a point to point distance of

    tan(a/2) = (d/2)/l

    d = tan(a/2) * l * 2 = tan(3.66*10^-4) * 24100 * 2 = 8.8 m

    So in conclusion, with regular, human-like eyes he could discern points that are at least 8.8 m apart in the best case scenario. Discerning hair color from the color of the clothes would need a much higher resolution, and the horsemen are probably not 10 m apart from each other either. And again, this is a theoretical limit, real-world resolution would probably be significantly lower.
















  • 1 kW is 3412 BTU/h (=BTUs)

    Most induction stovetops have a boost function with around 3-4 kW (that’s about 13000 BTUs).

    BUT contrary to a gas stove top, almost all of the energy is actually put into the pot instead of the surroundings (only 30-40% of the energy from a gas stove is used to heat the pot). Meaning that a 4 kW induction cooktop should be comparable to a 40’000 BTUs gas stove (single burner).