Good explanation of volts, amps and battery life

farnzo;6166075 said:

What mah means exactly is milliamps times hours. I won't go into algebra here but nothing in front of the h means that there is a 1 there. So, if you have a 900ma battery it can put out a constant 900 milliamps for one hour. If you know the metric system then you know that 900ma is equal to .9amps, if not congratulations you live in Kentucky. Let's say you have a 1.8 Ohm atomizer and a 3.7 Volt 900mah battery. Use a little Ohm's law here to find out how many amps your battery is putting out when you push the button. 3.7 Volts divided by 1.8 Ohms = 2.06 amps. Now take .9 and divide it by 2.06 and it equals .437. Now take .437 times 60 and you get 26.22 and take .22 times 60 and you get 13.2. But, what does it all mean astronaut farmer? It means that if you push down the button on an e-cig with a 3.7 Volt 900mah battery with a 1.8 Ohm atomizer attached for a total (not all at once of course) of 26 minutes and 13.2 seconds, your battery will die. Think about it before you doubt it, you only hold the button down three seconds at a time. So, about 20 puffs per every minute the button is pressed times 26.22 minutes equals 524 puffs on that combination of hardware. I'm thinking I might make this into a handy excel spreadsheet that you could plug the Volts, mah, atomizer resistance, and average puff length, so you can see how long your setups will last?

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