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State Ohm's law. Draw a labelled circuit...

State Ohm's law. Draw a labelled circuit diagram to verify this law in the laboratory. If you draw a graph between the potential difference and current flowing through a metallic conductor, what kind of curve will you get? Explain how would you use this graph to determine the resistance of the conductor.

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Ohm's law states that the electric current, through a conductor, is directly proportional to the potential difference across its two ends when, other physical condition like temperature, etc., remain constant.
`V prop I`
`or (V)/(I) = "Constant" = R`
`or V = IR`
Thus, the ratio V : I is a constant. This constant is called the resistance (R) of the conductor.
Circuit diagram for Ohm's law:

Explanation. If a graph is drawn between the potential difference (V) and current (I), the graph is found to be a straight line passing through the origin. This shows current is directly proportional to the potential difference. Thus the ratio `(V)/(I)` remains constant. This constant is called the resistance of the conductor. The gradient of the straight ling graph is related to the resistance (R) of the conductor.
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