Hi Tony,
"... 100 knots is about 55mph ..."
Assuming you meant Kilometers/Hour (based upon the context), it's
actually 62.5 MPH.
Regards,
David
On 2020-07-21 12:00, Tony Thigpen wrote:
It's all perspective and how precise you need to be. And what we are
measuring.
The only thing I know that is measured in yards is cloth and football.
In football, we never measure in feet or inches, just yards. We just
care if it crosses the line.
For construction, we never use yards, it's always feet. It can be 300
feet and we still call it feet. We don't convert it to yards.
In home improvements, boards and such are measured in feet,inch,16ths.
That is it. Not yards,feet,inch,16th.
When driving down the road, it's all miles or 1/10 of a mile. We don't
say Mile,yard,feet,inch,16th.
When I am flying my plane, I only care about height in 100 feet
increments. If I say I am at 3100 feet, that can be anywhere between
3050 and 3150. And, if I am talking to ATC, its "N1234 level at 3.1".
And, speaking of flying, I fly in KPH , not MPH. I don't don't convert
between knots or miles, I just use what is applicable.
When I drive in Canada, I just use the other markings on the
speedometer. I know that 100 knots is about 55mph, but I don't really
care as I don't convert it back and forth. I just go by what the sign
says. (Which, as a good American, I add 10 to, or maybe 20 if I am on
an interstate highway.)
So, as a USAns (as someone called us), we don't worry about conversion
between lengths that much. So, that is why the whole "must be base 10"
issue does not matter to me.
Tony Thigpen
David Crayford wrote on 7/21/20 9:57 AM:
I agree that cups are useful! The only time I find Imperial useful is
reading US recipes that use cups. Other than that Imperial is brain
damaged! And I say that having grown up in the UK to a family which
used Imperial all the time in my youth.
I used to go to the sweet shop and ask for a quarter of a pound of
American hard gums!
I recently watched a US home improvements show and couldn't fathom
how anybody could make sense of 1/16th of an inch. I couldn't tell
you how many yards to a mile but meters to a KM is simple.
On 2020-07-21 9:46 PM, Pew, Curtis G wrote:
On Jul 20, 2020, at 10:22 PM, Jackson, Rob
<rwjack...@firsthorizon.com> wrote:
American standard--Imperial units; they're rubbish. Abject
garbage. SI is not a fad, despite its origins. No fan of the
"French;" no fan of "Trump;" no fan of anything political. But SI,
revised a couple times or three, is a beautiful system of units in
which one may compute physics. If you disagree, then I assert you
have a challenge understanding many things about physics. I'm
talking about mechanics and fluid dynamics. I'm too stupid for
E&M, although the same equivalency attempts apply there.
For science and engineering I totally agree: you should never use
anything but SI units. They have precise definitions, and being
decimal-based make calculations easier. Not to mention being used
world-wide.
For everyday life, though, I think American/Imperial units (and any
other traditional systems that may survive elsewhere) have their
advantages. They evolved because people found them useful. For
example, when I’m cooking I could say 250 milliliters or one cup
(they’re close enough for the precision I need) but one cup is
simpler. Or if my pedometer says I’ve walked 2000 steps I know I’ve
gone about a mile. (“Mile” comes from “mille passuum” = “a thousand
of steps”; my pedometer counts left and right as separate steps but
for the Romans you had to move both before they counted it.)
P.S. Apparently Imperial units have been redefined as relative to
SI. Imagine that.
Yep. For precision definitions, always use SI.
I think it’s cool that SI units are now defined by specifying exact
values for physical constants.
P.P.S. This reminds me of many conversations with my father. He
absolutely couldn't stand this type of thing, i.e. SI being
obviously superior. I don't get it. It is what it is.
As a disclaimer, I'm not a complete bigot. I say miles and yards;
but I have this nasty habit of converting them to meters in my mind
every time I say them. The one thing I cannot get used to in
every-day life is Celsius degrees. I think in Fahrenheit degrees.
Oddly enough, since they're exactly the same thing, I find it
easier to talk in Kelvins rather than Celsius degrees. Maybe I
just like starting at zero. :) I couldn't tell you what absolute
zero in Fahrenheit is; I guess I never cared.
This supports my point about the convenience of traditional units.
Fahrenheit is more granular than Celsius, so you can be a bit more
precise without having to go to decimals.
----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
.
----------------------------------------------------------------------
For IBM-MAIN subscribe / signoff / archive access instructions,
send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
