# Voltage as a function of current

- Author:
- Allen Olson

If we treat current as the input, it is plotted on the horizontal axis.
If we take voltage to be the output, it will be plotted on the vertical axis.
According to Ohm's law, resistance is the connection between current and voltage.
GeoGebra has a nice feature that allows you to see how the graph will look with different values of a particular "constant" or coefficient. It creates a "slider" that you can adjust.
Click and drag the dot next to "R=" in the graph below. What does it do to the plotted line?

In the plot above, set the resistance to 40 (which we take to mean 40 ). What current would flow if the voltage was a) 40 V, b) -80 V, or c) 60 V?

In the plot above, set the resistance to 100 . Estimate the current shown on the graph for voltages of a) -20 V, b) 40 V, and c) 60 V.