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    So for part B, it asks for the resistance of the resistor.

    I get an answer of 6.7, from 2/0.3

    but it is saying the answer is wrong. Can you work it out please.

    https://isaacphysics.org/questions/p...haracteristics
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    (Original post by YourGoddamnRight)
    So for part B, it asks for the resistance of the resistor.

    I get an answer of 6.7, from 2/0.3

    but it is saying the answer is wrong. Can you work it out please.

    https://isaacphysics.org/questions/p...haracteristics
    The voltage across the bulb is 2.0V from the characteristic curve... which means that the voltage across the resistor is 4.0V
    because Vbulb + Vresistor = Vbattery

    the question is asking for the value of the resistor, so you don't want to use the voltage across the bulb in your R=V/I calculation.
 
 
 
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