The last of the original standard meters can still be seen in Paris:
Today the meter is defined as,
https://physics.nist.gov/cuu/Units/current.html#:~:text=meter,in%20terms%20of%20ΔνCs.
Meters per second (m/s) is the SI unit for velocity and the unit recommended by the World Meteorological Organization for reporting wind speeds, and is amongst others used in weather forecasts in the Nordic countries.[2] Since 2010 the International Civil Aviation Organization (ICAO) also recommends meters per second for reporting wind speed when approaching runways, replacing their former recommendation of using kilometers per hour (km/h).[3] For historical reasons, other units such as miles per hour (mph), knots (kn)[4] or feet per second (ft/s) are also sometimes used to measure wind speeds. Historically, wind speeds have also been classified using the Beaufort scale, which is based on visual observations of specifically defined wind effects at sea or on land.
That’s certainly easier to remember than the length of your foot (I wear size 12, a foot long. No idea what that is metric, maybe something in the 40s. It’s size 29 in “mondo” (ski boots).
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Just to make it easier, US and UK have different shoe sizes
https://www.candefashions.com/about/shoe-size-conversion-chart/
That’s certainly easier to remember than 1 m/sec is about 2 knots.
As long as we’re on the subject of measurements, how about we end the madness and stop moving clocks back in the fall.
That’s what I do; multiply the m/s by two to get kts., which is what I’m used to think in when it comes to wind speed. Could that be because of my seafarer background?
Anecdote:
On a J/U rig in the Java Sea we were Waiting on Weather (WOW) to move during the NE Monsoon.
The Companyman came up to the Jacking Control Room, looked out at the wind sock and said; “stiff as a preacher’s dick in a double wedding. We ain’t moving nowhere today”.
Then he went back to his office and his game of Solitaire.
PS> Difficult to find a conversion table with that wind speed measuring unit.
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11 posts were split to a new topic: Time changes
But the Navy uses yards for everything, no matter where in the world they are.
Is it a ploy to confuse the enemy?
Something like using Navajo natives to communicate in their native language during WWII.
Nobody understood what the hell they were talking about either.
I’m not even sure the Navy knows what they’re talking about never-mind anybody else.
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The standard unit for pressure in the SI system is the Newton per square meter or pascal ¶
Source:
The SI unit of force is the newton, symbol N.
Force is defined as the rate of change of momentum. For an unchanging mass, this is equivalent to mass x acceleration.
So, 1 N = 1 kg m s-2, or 1 kg m/s2.
Source:
PS
nautical mile is now 1852 meters, mariners lost that argument
I think the Navy is hooked on “yards” because of the close equivalence of 1 nautical mile (6067 ft) to 2000 yds., which makes it easy to mentally convert ranges from yards to miles. I say that because in my limited experience observing on Coast Guard Cutter bridges (which I got to do every now and then in the PHS), I seem to recall that I rarely heard a range called in anything but a multiple of 500 yds (¼ mile). I’m not sure, but I’d guess that the rings on their radar scopes and maneuvering boards or screens are marked at 500 yd intervals.
The only force unit I’ve ever seen aboard ship was Kilonewton for rating crane capacity. The simplest conversion is 10 kN ≈ 1 metric ton-force.
The conversion is based on standard gravity which is 9.80665 m/s2 which rounds to 10.
ever seen the weight of a container in Newtons?
Strictly speaking it’s not weight but force. That’s why the conversion is to metric ton-force and not metric tons.
A crane rated at 98 kN is rated at about 10 metric tons.
Even the inch is a metric unit these days, defined as 25.4 mm. Is there actually a single imperial unit out there that are not defined as some conversion of a metric unit?
My understanding is that the system that the U.S. uses is
United States customary units
Wikipedia says this:
The majority of U.S. customary units were redefined in terms of the meter and kilogram with the Mendenhall Order of 1893 and, in practice, for many years before.[2] These definitions were refined by the international yard and pound agreement of 1959.[3]
Interesting quote from the Containertech article Ombugge posted in the other thread: " The overwhelming need to have a standard size for containers, in order that they fit all ships, cranes, and trucks, and the length of time that the current container sizes have been in use, makes changing to an even metric size impractical."
That might be applied to other areas of endeavor as well.
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