3 ms·

I know this is off-topic, but I'm curious. I always had the impression that even in the US, standard units are used for engineering. Reading about "ft-lb" makes

I know this is off-topic, but I'm curious. I always had the impression that even in the US, standard units are used for engineering. Reading about "ft-lb" makes me think I was wrong (and my head hurt, tbh). Do you really compute stuff like torque in imperial units? Don't you need weird factors in every formula to make that work?

bluGill 3y ago
There are lots of weird factors in engineering anyway. We have different factors, but there are still factors. Besides, nobody is calculating this, they are measuring and that is just a matter of what label you put on the dial. Most engineering in the US is done in metric units. Then marketing applies a metric to imperial conversion. I suspect China does more engineering in imperial than the US, both in total an per capita: most things I buy made in America are all metric (cars are all metric except for parts designed in the 1960s and the adapter bracket to make them fit on a modern metric car). Most things I buy made in China are imperial. I don't really know for sure, but that is my impression of industry.
- codeflo 3y ago
  > Besides, nobody is calculating this, they are measuring and that is just a matter of what label you put on the dial. That's why I asked about engineering, not driving. Nobody converts torque to power etc.?
  - bluGill 3y ago
    The engineers who do that are using metric. Marketing might do this conversion, but they just plug it into a converter and have no reason to know anything more than bigger is better.
  - mcronce 3y ago
    Torque to power is just (torque * RPM) / (some constant depending on the units inolved). With ft-lbs and horsepower, that constant is 5252; with N-m and kW, it's 9549. The only thing that changes is the constant.
    - codeflo 3y ago
      You make it sound like you'd have to remember a 4-digit constant in either case. That's stupid, it's simply (torque * RPS * 2 * PI).
    - raketenolli 3y ago
      No, power is just torque times angular velocity. No constants involved.
      - mcronce 3y ago
        If you ignore units, sure.

bluGill 3y ago

There are lots of weird factors in engineering anyway. We have different factors, but there are still factors. Besides, nobody is calculating this, they are measuring and that is just a matter of what label you put on the dial. Most engineering in the US is done in metric units. Then marketing applies a metric to imperial conversion. I suspect China does more engineering in imperial than the US, both in total an per capita: most things I buy made in America are all metric (cars are all metric except for parts designed in the 1960s and the adapter bracket to make them fit on a modern metric car). Most things I buy made in China are imperial. I don't really know for sure, but that is my impression of industry.

codeflo 3y ago
> Besides, nobody is calculating this, they are measuring and that is just a matter of what label you put on the dial. That's why I asked about engineering, not driving. Nobody converts torque to power etc.?
- bluGill 3y ago
  The engineers who do that are using metric. Marketing might do this conversion, but they just plug it into a converter and have no reason to know anything more than bigger is better.
- mcronce 3y ago
  Torque to power is just (torque * RPM) / (some constant depending on the units inolved). With ft-lbs and horsepower, that constant is 5252; with N-m and kW, it's 9549. The only thing that changes is the constant.
  - codeflo 3y ago
    You make it sound like you'd have to remember a 4-digit constant in either case. That's stupid, it's simply (torque * RPS * 2 * PI).
  - raketenolli 3y ago
    No, power is just torque times angular velocity. No constants involved.
    - mcronce 3y ago
      If you ignore units, sure.