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Amp question

by david90
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david90
#1
Apr10-04, 02:47 AM
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How long will a device drawing 8 mA last on a 12 v bat that has a 25mAh?


25/8 = 3.125 hours?
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chroot
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Apr10-04, 02:52 AM
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You got it.

- Warren
david90
#3
Apr10-04, 03:03 AM
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is there a bat as small as a watch bat that can produce that much mAh at 12v?

chroot
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Apr10-04, 03:07 AM
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Amp question

Not that I know of.

- Warren
david90
#5
Apr10-04, 03:17 AM
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what is ur mAH for watch bat?
chroot
#6
Apr10-04, 03:24 AM
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Hell if I know, but I've never seen a 12V watch battery. Most battery chemistries in use today are 1.5 volts or so -- they'd have to pack 8 cells into that watch battery package to get 12V, and I don't think it's been done.

- Warren
hitssquad
#7
Apr10-04, 05:11 AM
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http://www.google.com/search?q=%22wa...22+lithium+mah
hitssquad
#8
Apr10-04, 05:21 AM
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Quote Quote by david90
How long will a device drawing 8 mA last on a 12 v bat that has a 25mAh?
Voltage is electrical pressure, and it is analogous to water pressure. We don't need to know what the voltage is to answer this; we just need to know that it is considered consistent throughout the problem. The question should be stated as:How long will a device drawing 8 mA at a particular given voltage last on a battery that has a capacity of 25mAh at the same given voltage?.



25/8 = 3.125 hours?
Yes, if the question is stated as I corrected above.


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