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1 resistor

  1. Jun 2, 2012 #1
    This may sound a little silly but I have a circuit with 1 resistor which is a 1k ohm resistor
    and is connected to a 9 Volt battery.I found the amps using ohm's law I = E/R which equals 9 amps.I have also used a multi-meter to see the resistance and I'm a bit confused a resistor is supposed to resist so what is 1 resistor resisting?

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  3. Jun 2, 2012 #2


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    The current should be 9 mA or 0.009 Amps. using Ohm's law I = E / R,
    I = 9 volts / 1000 ohms = 0.009 amps or 9 mA.

    The resistor "resists" the current flow being a lot greater than 9 mA.

    A 9 volt battery can't supply infinite current because it has internal resistance, but it can supply 0.5 amps for a short time before it goes flat.

    Do you have a problem with the naming of resistors? It is just a name. I guess there was a historical reason for naming them like that, but it doesn't matter much as long as you know what device they are talking about
  4. Jun 5, 2012 #3


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    Passing a current through a resistor requires Power.
    Rather than saying that a resistor "resists" it's probably better to say that a resistor Dissipates (uses up) electrical power. A voltage V will cause a current I to pass through a resistor R and the resistor will be dissipating VI Watts of power at this time.
    Notions of Force and actual Movement tend not, actually, to be very helpful when discussing most aspects of electricity, although they may be attractive ideas, at first sight.
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