• @[email protected]
    link
    fedilink
    English
    53 months ago

    You might’ve already seen this, but try using the method of dimensional analysis where you work backwards on a single line and you’ll never get one of those problems wrong again.

    The key is just working backwards by units using the equations you have available. I know somebody that only got one of the questions on his MCAT correct bc he used this method lol.

    • @[email protected]
      link
      fedilink
      English
      9
      edit-2
      3 months ago

      I use dimensional analysis, but it’s over two lines… and not sure what you mean by working backwards, since the order doesn’t really matter so long as every value is in the correct line.

      Since typing it out would be ugly as sin, example image stolen from google:

      …they like to give us things like pt weight in lbs and oz, and ask for final product of tablespoons or some shit cuz they enjoy wasting our time, lol.

      That the type you mean?

      I know there are a few different ways to crunch the numbers, but DA is my favorite so far cuz it’s so consistent.

      *edit, example pic changed, first one put mcg twice in the same line, which is a weird move. /shrug

      • @[email protected]
        link
        fedilink
        English
        33 months ago

        So USAnian drugs are in metric units? I hope in actual work nurses get to use a phone app or something because this asks for mistakes

        • @[email protected]
          link
          fedilink
          English
          103 months ago

          99% of it is metric. I think the biggest outlier is home care, where you go visit some grandma who’s actively offended by metric, so if you tell her to take 7.5mL of something she’ll just do the deer in the headlights thing, then shove the bottle up her ass.

          Tell her instead that she needs to take 3 Mountain Dew caps full and suddenly she can follow instructions enough to not kill herself.

          • @[email protected]
            link
            fedilink
            English
            23 months ago

            I thought everything is bigger across the ocean but your Mountain Dew caps are tiny over there! ;)

            • @[email protected]
              link
              fedilink
              English
              33 months ago

              Just googled it and apparently they’re about 5mL each. Apparently I’m not great at eyeballing volume.

              Add it to the pile of conversion failures between metric and imperial.

              • @[email protected]
                link
                fedilink
                English
                13 months ago

                Yeah, 5ml is a teaspoon, but I’m not sure if it’s reasonable to assume teaspoons have similar sizes across countries.

                But after your first month in the job you’ll convert and eyeball it even when half asleep :)

                • @[email protected]
                  link
                  fedilink
                  English
                  13 months ago

                  I know it should be obvious and maybe I missed the sarcasm, but the teaspoon unit is in no way the same as an actual teaspoon utensil. I also don’t use my own feet to measure length.

                  • @[email protected]
                    link
                    fedilink
                    English
                    13 months ago

                    I didn’t think that was sarcasm, it’s just such a jacked up system of measurement that he’s not confident it doesn’t change with borders, which is honestly a pretty reasonable point of uncertainty.

        • @[email protected]
          link
          fedilink
          English
          73 months ago

          Even in the US, science is mostly metric. But most US people are not exactly the scientific kind…

          • @[email protected]
            link
            fedilink
            English
            23 months ago

            Modern science is, but there’s plenty of old journals from the 80s and earlier that use degrees Rankine and gallons.

            • @[email protected]
              link
              fedilink
              English
              3
              edit-2
              3 months ago

              Fucking BTUs and shit.

              PSI is another one that seems to be used over the metric/SI alternative in some science-adjacent applications.

              • @[email protected]
                link
                fedilink
                English
                13 months ago

                Psi is used a lot in engineering. But honestly, pressure units are a bit of a mess. The metric unit is a Pascal, which is fundamentally defined as a Newton per square meter – unsurprisingly, that is an incredibly small quantity of pressure. It’s roughly 101,500 Pascals for standard atmospheric pressure. You’ll typically see pressure written in either kPa, MPa, or bars (1E5 Pascals) within a metric framework. For perspective, it’s 14.7 psi (lbs per square inch) for an atmosphere.

                And personally, I think all of these are pretty silly when we could be using 1 atm instead, which is literally defined as standard atmospheric pressure. It’s a much easier way to visualize and intuitively grasp pressures.

                BTU is another fun one. It’s the energy needed to raise 1 lb of water by 1 degF. Calorie is the energy to raise 1 g of water by 1 degC. Both are very pragmatic definitions and have a degree of intuition. Then they’re the metric unit, the Joule, which suffers from the same issue as Pascal. It’s the work done by a 1 Newton force pushing an object 1 meter. Once again, pretty small.

        • @[email protected]
          link
          fedilink
          English
          23 months ago

          It works fine when everything around you is in those numbers. The scale for medications might be set to mg, or injections in mL. The bottles for both are labeled the same way. Everything works together, and you don’t really have to think about it.

          Part of the problem with converting everything to metric is it really needs to be everything. You can try talking about driving distances in km, and your gas tank in L/100km, and your speed in km/hr. However, the interstate highway signs will still be in miles, you buy gas in gallons, and the speed limit signs are in mph. This isn’t a case where you can just choose to use the metric system as an individual, because the whole system works against you.

          • @[email protected]
            link
            fedilink
            English
            13 months ago

            That is understandable, I was surprised that metric is actually used somewhere. Use in pharmacy also explains why in Hollywood stoner comedies they used grams, which always confused me.

            • @[email protected]
              link
              fedilink
              English
              13 months ago

              It’s used all over the place in the US. It’s usually a weird, thoughtless mixture. Milk is sold in gallons, soda is sold in liters.

              In fact, you’ll find exceptions in most countries once you start looking for them. Just a matter of how prevalent the metric system is; nobody is 100%. Most common exception is car tires because of how industry standards work.

        • @[email protected]
          link
          fedilink
          English
          13 months ago

          Gotcha! Yeah same page - some of the other students don’t like that method cuz it can take a bit longer, but building the equation kinda idiot proofs itself against calculating for the wrong unit, and it’s super consistent! Definitely my favorite so far.

    • @[email protected]
      link
      fedilink
      English
      83 months ago

      Even dimensional analysis works best with metric because sometimes you need to convert units and almost all conversion in metric are base 10, so something like 1kg/km is 1000g/1000m is 1 gram per meter. But in imperial 1 pound/mile is 16 ounces / 5280 feet is who the fuck knows how many ounces per feet.