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convert to watt? Answered

I am thinking of buying a acid battery. Its specification says that it is a 12 volt one and it's AHC@20 is 200.
Can anybody calculate the watt output. I am not sure but AHC stands for Ampere hour capacity.

Thanks
RajibAzam

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seandogue (author)2014-10-06

If you're asking what it's maximum power output is, and presuming little or no voltage droop over the course of some acion, then it's simply the nominal voltage times the rated maximum load current (see its spec sheet for that value)

Of course, I'm guessing, since as stated, your question has no logical meaning. Watts implies action (an expenditure of kinetic energy by some source or the energy required to start, maintain, or stop some action in some load), but batteries are by themselves, and in the absence of an electrical load (at least ideally) all potential energy and no kinetic.

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seandogue (author)seandogue2014-10-06

(Note that without a load, Ibattery = 0)

therefore,

P= I x V

=> P = 12V x 0A

=> P = 0

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JM1999 (author)2014-10-05

To convert to any sort of electricity you need to use ohm's law.

To use it you need two of the measurements (ie. volts and amps)

The following is the formula you would use:

The formula for Watts is Volts times Amps.

12 Volts multiplied by 5 Amps equals 60 Watts.

The formula for Volts is Watts divided by Amps.

60 watts divided 5 Amps equals 12 Volts.

The formula for Amps is Watts divided by Volts.

60 watts divided by 12 volts equals 5 amps.

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kelseymh (author)JM19992014-10-05

What you describe is not Ohm's law. Ohm's law describes the empirical relationship between voltage, current and resistance, and is written V = I*R.

What you've written above are just the definitions of the SI units of voltage, current, and power.

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JM1999 (author)kelseymh2014-10-05

Right, I always thought it was ohm's law, I must change my whiteboard out!

It is written on a white board on the wall so when I want another electrical appliance I just refer to the chart so I know if the electrical system can handle it.

Thanks for pointing that out, I hate to lead others astray.

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kelseymh (author)JM19992014-10-06

There is a power equation derived from Ohm's law: P = R*I^2. Just take Ohm's law and multiply both sides by current; P = V*I by definition (hence the rule for SI units), and (I*R)*I = R*I^2. P=V*I because I = Q/t (current is charge per unit time), V*Q = E (voltage*charge is energy), so V*I = V*Q/t = E/t, and power is just energy per unit time. It's all just algebra :-)

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Aziz7264 (author)2014-10-05

perhaps you got the wrong specs bro. AHC. AH stands for ampere hour that's true. but "C" is a unit to indicate discharge rate of a typical battery.

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