On a test in college I was asked to find the current flowing through a resistor and lightbulb on a simple circuit with a battery, resistor and lightbulb. I was told the resistance of the resistor and was given a voltmeter so I measured the voltage across each of the components but when it came to calculating the current I couldn't because I didn't know the resistance of the lightbulb. I'm assuming I could have calculated its resistance since I knew the voltage drop caused by the resistor since I knew the resistance of the resistor. How would you go about calculating the resistance of a component when you know the voltage drop caused by it?(adsbygoogle = window.adsbygoogle || []).push({});

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# Calculating resistance from voltage drop

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