Finding Resistance of Ohmic Resistor with Voltmeter and Household Items

AI Thread Summary
To find the resistance of an unknown ohmic resistor using a voltmeter and household items, one can set up a simple circuit, but it requires careful consideration of the tools available. Most voltmeters can measure resistance directly, but if only voltage measurement is possible, alternative methods must be explored. Using household appliances may involve disassembling them to retrieve components like batteries or resistors, which can be measured for reference. Caution is advised against using the resistance of a light bulb based on its voltage and power ratings, as this can yield inaccurate results at room temperature. Accurate resistance measurement requires a clear understanding of the circuit and components involved.
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Can someone explain how I can find the resistance of an ohmic resistor of unknown resistance by setting up a simple circuit using a voltmeter and household appliances? Thanks
 
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What are your thoughts on how to approach this question? The simplest answer is that most voltmeters have resistance measuring capability, but I'm pretty sure that's not the answer that folks want you to come up with. If the meter can only measure voltage, and you only have one unknown value resistor (and no reference resistor), then what else can you do? What does the question mean by "household appliances"? Can you take them apart and take out batteries, cut out resistors that you can read the color code on to figure out their resistance and use them as references? What?
 
I hope whoever posed the question is not thinking of using the resistance of a light bulb calculated from it's voltage and power ratings. That resistance calculation would actually be wrong at room temperature.
 

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