This may sound like a stupid question but how can you tell the difference between a variable capacitor and a variable resistor. I have a multi meter that can measure resistance and capacitance but I get varying measurements when I measure either part on both settings.
One way you could tell the difference is to connect a battery and light w/ the capacitor and then the resistor in series. The resistor will only dim the light, while the capacitor will stop the light all together. Capacitors do not allow dc current through, only ac.