Consider a simple rc circuit, with the battery, resistor, and capacitor connected in series. suppose you want to use the oscilloscope to measure the current through this circuit as a function of time. how can you do it how can you do it? (remember, the oscilloscope can only be used to graph the voltage across one or more circuit elements.) we want the graph to have the right general shape; but it need not be scaled properly. in other words, it can be "too tall" or "too short", as long as it has the right shape.