According to Ohm's Law, R. = V/I, the physical meaning of slope for voltages vs current graphs is resistance.
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In a graph of voltage vs. current, the graph would be a straight line, and the slope of this line would be the device's resistance.
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I think you've got it! The slope is defined as the change in y divided by the change in x. In this case, it would be your change in voltage/change in current. Ohm's law gives you
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Impedance, similarly to resistance, equals maximum voltage divided by maximum current. The plot will be an ellipse if a constant AC voltage is applied. It's an ellipse because voltage
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