Variable capacitors (capacitive microphone)
simulate this circuit &ndash; Schematic created using CircuitLab

Your instructor is right :) Impedance of capacitor is inversely proportional to it's capacitance.
$$
V_{out}=V_{cc}\frac{\frac{1}{j\omega C_{2}}}{\frac{1}{j\omega C_{2}}+\frac{1}{j\omega C_{1}}}=V_{cc}\frac{C_{1}}{C_{2}+C_{1}}
$$

The picture illustrates transient response of the divider. Verical is Vout and horisontal is time. At the first moment output is determined by C1/C2 ratio, but after long time (after relaxation) it determined only by R1/R2 ratio.