Calculate the current being drawn from a battery

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    Battery Current
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Homework Help Overview

The discussion revolves around calculating the current drawn from a battery, focusing on the relationship between voltage, resistance, and current in the context of electrical circuits.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • Participants discuss the appropriate units for current and resistance, with some exploring the use of Ohm's Law and power equations to derive current from given voltage and resistance values.

Discussion Status

Participants are actively engaging with the concepts, with some expressing uncertainty about their understanding and seeking confirmation on their reasoning. There is a mix of approaches being considered, including the use of Ohm's Law and power formulas.

Contextual Notes

Some participants mention having specific values for voltage and resistance, while others express confusion about the relationships between these quantities and the units involved.

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,

[tex]P = E I[/tex]

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

[tex]I = \frac{P}{E}[/tex]

You could save yourself a step and use

[tex]I = \frac{E}{R}[/tex]
 
Last edited:

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