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


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

- Warren
david90
Apr10-04, 03:03 AM
is there a bat as small as a watch bat that can produce that much mAh at 12v?
chroot
Apr10-04, 03:07 AM
Not that I know of.

- Warren
david90
Apr10-04, 03:17 AM
what is ur mAH for watch bat?
chroot
Apr10-04, 03:24 AM
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
Apr10-04, 05:11 AM
http://www.google.com/search?q=%22watch+battery%22+lithium+mah
hitssquad
Apr10-04, 05:21 AM
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.