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qim
Jan1-04, 01:18 PM
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

Jimmy
Jan1-04, 03:33 PM
Resistance is measured in ohms. Current is measured in amps.

qim
Jan1-04, 04:26 PM
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

Mathechyst
Jan1-04, 04:36 PM
Wouldn't it be easier to use Ohm's Law?

Doug

qim
Jan1-04, 04:58 PM
Thanks Doug

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

Yes, I got it, thanks very much.

qim

Jimmy
Jan2-04, 12:26 AM
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}