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Old January 31st 12, 03:32 PM posted to rec.aviation.soaring
JohnDeRosa
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Posts: 236
Default Typo in Battery Test Article in Soaring

Well heck. A typo crept into my "Battery Test" article in the
February issue Soaring. So for those checking my math in footnote #1,
this is how it should have read;

"1A is the nominal current draw at 12Vdc (12W). When the
battery voltage drops below 12Vdc, the current draw is lower. Above
12Vdc, the current draw is higher. For example, at 11Vdc a 12ohm load
draws 0.92A (10.1W) and at 13Vdc a 12ohm load draws 1.1A (14.1W)."

And if someone rechecks this math they will find that P = E x I = 13 x
1.1 = 14.3W. So how did I come up with 14.1W? Because I = E/R =
13/12 = 1.08333 which I rounded to 1.1 which would give 14.3W. But
actually P = 13 x 1.08333 = 14.1W. Watch those significant digits!

Sigh.

- John DeRosa