Q23 of 30 Page 1

A V-I graph for a nichrome wire is given below. What do you infer from this graph? Draw a labelled circuit diagram to obtain such a graph.


The graph suggests that the current flowing in the conductor is directly proportional to the potential difference across the conductor.

The slope of the graph is the resistance of the conductor.


R = (V2 - V1)/(I2 - I1)


R = (0.8 - 0.4)/(0.3 - 0.2) = 0.4/0.1 = 4 ohm


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