[aprssig] Metric [[furlongs ... Appology
Glenn Little WB4UIV
glennmaillist at bellsouth.net
Sat Sep 8 00:26:08 EDT 2007
Somewhere in this thread, someone mentioned time and why we did not use 10
hours vs 12 hours.
A circle has 360 degrees, why I do not know. A day is defined as 24 hours
(sort of). As the earth really rotates at 15.04 degrees per hour (plus or
minus, due to drag of the wind on mountains and waves at sea), the day is
really 360 divided by 15.04 or 23.936 hours. To correct for the difference
between 24 hours per day and 23.936 hours per day, we have a leap year
every four years unless it is a century year (ending in 00) where we forget
the leap year (there are some other conditions to delete the leap year).
If we changed to a metric hour day of 10 hours, we would have to change a
lot of navigation calculations (15.04 is a defined navigational constant
known as earth rate). We would have to redefine the calendar to eliminate
leap year. WE would have to reeducate a lot of people (it was really hard
to educate a lot of them the first time around).
Probably easier to leave it the way it is, rather than confuse a lot of
people, spend a lot of money redefining navigation, filling the landfill
with all the old clocks and probably some other consequences.
On the other hand it would create some more jobs getting all these changes
accomplished.
FWIW
73
Glenn
WB4UIV
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