• mkwt@lemmy.world
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    4 个月前

    This is actually pretty important to being able to solve engineering problems in the real world. Invariably, every little sub industry has its own cursed unit system. And dimensional analysis is great for solving real problems on its own.

    And if you get to a high enough physics level, they start setting hbar = c = 1 or G = c = 1, and you never have to worry about it again.

    I’m the mean time, it’s worthwhile to learn the trick to do this stuff fast-ish.

      • Randelung@lemmy.world
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        4 个月前

        kWh has an intuitive reason. Watts are so small that you’d always calculate consumption in MJ and whatnot, and seconds are so short that you’d always be expressing time in ks. Using kWh will reduce the numbers to useful ranges and makes cancelling M and k unnecessary.

    • MisterFrog@lemmy.world
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      4 个月前

      I dislike that my highschool never once gave me the concept that units can simply be treated like constants to be cancelled out.

      I used to do the conversions for each variable before putting them in the equation like a fool.

      Now I’m slapping all of the conversions alongside the original values/units in a single expression like god intended.