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International System of Units overhauled in historic vote

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Re: International System of Units overhauled in historic vote

#61
post #35

Has a "metric" version of time ever been proposed? Seems odd to me that we're "ok" with divisions of 12 for time but not length. I guess for science seconds are basically the only measure of time that usually matters?

Heinlein's "Starship Troopers" has the space marines using "kiloseconds" and "megaseconds" conversationally, and it was always tricky for me to convert those to hours and minutes in my head accurately.

Re: International System of Units overhauled in historic vote

#62
post #35

Has a "metric" version of time ever been proposed? Seems odd to me that we're "ok" with divisions of 12 for time but not length. I guess for science seconds are basically the only measure of time that usually matters?

In scientific literature we do typically use one particular preferred time unit (second being the SI units) and then exponentiating properly (eg optically driven metal to insulator transition in V2O3 occurs in 1.3 picoseconds (10^-12 s), desorption of atmospheric gasses from CoPc thin film in vacuum takes ~10^5 s (~1 day)).

Re: International System of Units overhauled in historic vote

#63
post #47

Earlier quoted context omitted.

Is there any compelling reason why the US should switch to the metric system for daily use? Metric is already used universally in science and engineering, which seem to be the main fields in which consistency across countries matters. I completely agree that in physics, chemistry, engineering, medicine, etc., it is important to use standard units. But what harm is it doing in practice if in everyday life, Americans s…

> A good comparison is degrees Celsius, which are just as arbitrary/unscientific (the standard metric unit is the Kelvin). Celsius is literally the same scale as Kelvin, just shifted so that 0c = water freezing.

Yes, and water freezing is a totally arbitrary value.

Fahrenheit is scaled such that 0 is about the coldest it gets where I live, and 100 is about the hottest. (Very approximately, but close enough). That strikes me as a lot nicer in practice (since 99% of the time people are talking about temperature, it’s related to weather) than something based on the physical properties of a particular substance.

Also water freezing at 0 and boiling at 100 is only valid for a specific, non-metric, air pressure.

Re: International System of Units overhauled in historic vote

#64
post #60
post #47

Earlier quoted context omitted.

> A good comparison is degrees Celsius, which are just as arbitrary/unscientific (the standard metric unit is the Kelvin). Celsius is literally the same scale as Kelvin, just shifted so that 0c = water freezing.

Celsius is a particularly bad metric unit. It doesn't have enough units in the range most commonly encountered by humans, and it goes negative, which is also to be avoided in a good unit. So you end up needing negatives, and decimals.

[deleted]

Re: International System of Units overhauled in historic vote

#66

Earlier quoted context omitted.

Is there any compelling reason why the US should switch to the metric system for daily use? Metric is already used universally in science and engineering, which seem to be the main fields in which consistency across countries matters. I completely agree that in physics, chemistry, engineering, medicine, etc., it is important to use standard units. But what harm is it doing in practice if in everyday life, Americans s…

My Jeep is a bizarre combination of metric and SAE. ISS needs to have two sets of tools[0]. NASA lost the Mars Climate Orbiter due to confusion over the units of measure[1]. Patients are given the wrong dosages[2]. It seems safe to say it's a point of ongoing friction, especially on things like international trade. [0]: https://space.stackexchange.com/questions/12391/iss-nuts-and... [1]: https://mars.jpl.nasa.gov/msp…

I already made it clear that I totally agree metric should be standard in engineering or scientific applications. I wasn’t aware that this isn’t the case in the US — thanks for the info. I believe it is at least 95% the case in the US and I think we should make every effort to get that to 100%.

I still stand by my argument that it does not matter much for everyday life.

Re: International System of Units overhauled in historic vote

#67
post #35

Has a "metric" version of time ever been proposed? Seems odd to me that we're "ok" with divisions of 12 for time but not length. I guess for science seconds are basically the only measure of time that usually matters?

Heinlein's "Starship Troopers" has the space marines using "kiloseconds" and "megaseconds" conversationally, and it was always tricky for me to convert those to hours and minutes in my head accurately.

Odd choices... since 1000 seconds is ~17 minutes and 1M seconds is 4.6 hours.

Re: International System of Units overhauled in historic vote

#68

I guess the next redefinition will happen if and when there's detectable drift in "fundamental" constants?

I guess the next redefinition will happen if and when there's detectable drift in "fundamental" constants? And until then, all the metric fanbois will constantly tell you that metric is superior to imperial because its measurements are immutable. Until suddenly they are.

As opposed imperial constants? How is a foot standardized anyway? I suspect most manufactures rely on SI metrics for that.

Re: International System of Units overhauled in historic vote

#69
post #35

Has a "metric" version of time ever been proposed? Seems odd to me that we're "ok" with divisions of 12 for time but not length. I guess for science seconds are basically the only measure of time that usually matters?

Interestingly, a week can roughly be approximated as 10k minutes (with an error of less than 1%).

Re: International System of Units overhauled in historic vote

#70
post #35

Has a "metric" version of time ever been proposed? Seems odd to me that we're "ok" with divisions of 12 for time but not length. I guess for science seconds are basically the only measure of time that usually matters?

Heinlein's "Starship Troopers" has the space marines using "kiloseconds" and "megaseconds" conversationally, and it was always tricky for me to convert those to hours and minutes in my head accurately.

Also in the book "A Deepness in the Sky" by Vernor Vinge. In the beginning of the book there was a convenient chart for converting to our customary earthly time units.
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