Calculate the current being drawn from a battery

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    Battery Current
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Current drawn from a battery can be calculated using Ohm's Law, which states that I = E/R, where I is current in amps, E is voltage in volts, and R is resistance in ohms. The discussion highlights that while power can also be used to find current with the formula I = P/E, using Ohm's Law is more straightforward. Participants confirm that understanding voltage and resistance is key to solving the problem. The conversation emphasizes the importance of clarity in electrical measurements and calculations. Overall, using Ohm's Law simplifies the process of calculating current from given voltage and resistance values.
qim
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If I have a question asking to calculate the current being drawn from a battery can I, or rather should I, give an answer in Ohms?

I hate electricity...

Thanks and a Happy New Year to you all.

qim
 
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Resistance is measured in ohms. Current is measured in amps.
 
Hi Jim

Thanks, the penny is dropping...

I have been given the voltage and the resistances

So I guess I can work out the total resistance and then use P = V^2/R

and from there P = V/I > I = V/P

Just thinking aloud but I would be grateful if you could confirm that I am on the right track.

Thanks

qim
 
Wouldn't it be easier to use Ohm's Law?

Doug
 
Thanks Doug

"What's that?", you probably heard me say...

Yes, I got it, thanks very much.

qim
 
Originally posted by qim
Hi Jim

Thanks, the penny is dropping...

I have been given the voltage and the resistances

So I guess I can work out the total resistance and then use P = V^2/R

and from there P = V/I > I = V/P

Just thinking aloud but I would be grateful if you could confirm that I am on the right track.

Thanks

qim


Actually, E is more commonly used to symbolize voltage. The unit of measure for voltage(E) is the Volt(V). E = 10V for example. Anyway,

P = E I

So to calculate the current with a given Voltage and Power:

I = \frac{P}{E}

You could save yourself a step and use

I = \frac{E}{R}
 
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