Marta:
Read back. The old circle has 360 degrees, So the earth is divided
into 360 slices of mellon, and it takes the earth one whole day to
make the circle, so it takes 24 hours, which means that ever hour the
celestial noon moves 360/24= 15 degrees. Since one degree is 60
nautical miles then every hour the earth rotates 15 x 60 or 900 nm
per hour.
Every minute the earth rotates 60/60= 1 nautical mile.
Lets just try that in metric. The distance around a earth (assuming a
perfect sphere) is 24,874.56 km
Then it rotates 1036.44 km per hour.
And since you would like the hour to be 100 minutes, ok, it still
rotates 1036.44 per hour, or 10.3644 km per minute.
If a circle contained 100 degrees instead of 360 degrees, and each
degree had 100 minutes instead of 60, then you you can calculate that
every hour the earth would rotate 100/24= 4.1666 (or 2/3rds) km.
So guess what, with 4.1666, you are back to fractions again, and so
using the metric system has helped you one bit!
Neal Hammon
On Jan 44, 1120092007, at 7:35 PM, Marta Edie wrote:
We are going round and round. Why then are there 60 minutes in an
hour and not 100 ? All those ancient Babylonians and the like did
not know what they were doing!! They should have chosen metric!
But seriously, I am learning an immense amount of stuff here, it will
take me months to even get an inkling of what you all are spreading
before me. I am grateful to everybody. What a marvellous way to enter
into the New Year. ( And no, I did not spell "marvellous" wrong. I am
still hung up on the British spelling.
Marta
On Jan 4, 2009, at 19:04 pm, Jonathan Fletcher wrote:
On Jan 4, 2009, at 5:50 PM, Neal Hammon <[email protected]>
wrote:
PS: I reside in Shelbyville. Here in Shelbyville, where the court
house is at 85 degrees, 12.92 minutes west, celestial noon is a
little sooner, occurring at 12: 41 PM. And yes, Zulu time is one
hour behind most of the time set in Germany, but we can all live with
Zulu time and be happy.
Re. Time Zones
When I first moved to Louisville in the 80s I marveled at how the time
zone line on the map had this big bulge to the west around Louisville.
Indianapolis and Nashville, only slightly to the west of us were in
Central Time and we were in Eastern Time. Recently that has changed as
much of Indiana has chosen to join the Eastern contingent, but it is
remarkable how time zone boundaries are seemingly more a product of
politics than mathematics.
Re. Metric:
When I was more actively involved in the graphic arts industry, I
rejoiced that we were not using metric units for measuring document
layout. With 6 picas to the inch and 12 points to the pica it was a
breeze to divide the page into any useful even divisions--halves,
thirds, and fourths. Fifths were a problem but sixths were also easy.
Whole units, picas and points, would measure just about anything.
Metric would have required decimals places for common measurements on
a page. Even measuring in millimeters wouldn't be so neat and tidy.
Re. Time Zones, teil zwei:
My metri-centric German friend, the choice of 60 nautical miles per
hour at the equator is tied into the fact that there are 60 minutes in
an hour. The movements of our earth in the heavens dictated the early
division of time into days and hours. After that the distances on the
earth have replicated that hours and minutes system. A nautical mile
is equal to one minute of earth's rotation at the equator, which is a
sixtieth of a one-hour time zone. Having your time and distances very
precise was the only way to get around the oceans for many centuries
before satellite-based navigation, and likely still has a huge part to
play, but I don't have any current experience with that--my Navy days
seemingly being several lifetimes ago. BTW, the 0 degree longitude
runs right through the Greenwich Naval Observatory in England, which
is where we get Greenwich Mean Time. Them Navy guys is what caused all
this trouble, I tells ya!
j.
--
Jonathan Fletcher
FileMaker 9 Certified Developer
Project Foreman
NewMedia Construction Co.
[email protected]
Instigator
The BB&J Network
The "Go-To Guys" for
FileMaker Development in Louisville
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_______________________________________________
The next Louisville Computer Society meeting will
be January 27 at MacAuthority, 128 Breckinridge Lane.
Posting address: [email protected]
Information: http://www.math.louisville.edu/mailman/listinfo/macgroup
_______________________________________________
The next Louisville Computer Society meeting will
be January 27 at MacAuthority, 128 Breckinridge Lane.
Posting address: [email protected]
Information: http://www.math.louisville.edu/mailman/listinfo/macgroup
_______________________________________________
The next Louisville Computer Society meeting will
be January 27 at MacAuthority, 128 Breckinridge Lane.
Posting address: [email protected]
Information: http://www.math.louisville.edu/mailman/listinfo/macgroup
