[time-nuts] gravity controlled pendulumn clock?
Neville Michie
namichie at gmail.com
Tue Dec 13 22:10:37 UTC 2011
I find the biggest problem in units is when you want to solve a
physics problem and need
data on typical physical properties of substances, for instance
design of thermal insulation for an OCXO.
You can look through dozens of books with tables of typical values,
most of which are in units
of BTU/square foot/inch/hour, and a bewildering mixture of other
units, and are usually wrong!
Decimal points are slipped, or the values are reciprocals, or the
numbers have been lifted from a different
industry book that uses different units.
It is quite messy to have to measure these things from first principles.
At least with metric you can keep looking until you find 5 books that
agree, you can see the value with
the slipped decimal, and then you may have values that may be
reliable or at least stolen from the same source.
And you get your answer in Watts.
cheers,
Neville Michie
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