One Resistor, 9V Battery, and Ohm's Law: What is it Resisting?

AI Thread Summary
In a circuit with a 1k ohm resistor connected to a 9 Volt battery, Ohm's Law indicates the current should be 9 mA, not 9 amps. The resistor limits the current flow, preventing it from exceeding this value despite the battery's potential. The term "resistor" may be misleading; it is more accurate to say that a resistor dissipates electrical power rather than simply resists it. The internal resistance of the battery also plays a role in limiting the current output. Understanding the function of resistors in terms of power dissipation rather than resistance can clarify their role in electrical circuits.
Pin Head
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Hi,
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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Pin Head said:
Hi,
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?


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
 
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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