Which type of capacitor allows for adjustment of the distance between plates?

The trimmer type capacitor allows for the adjustment of the distance between its plates, which in turn changes its capacitance. This type of capacitor is specifically designed to fine-tune circuits by enabling small adjustments after the initial setup. Trimmer capacitors often have a mechanical adjustment mechanism, such as a screw or slider, that enables precise manipulation of the capacitor's value to achieve optimal circuit performance.

In contrast, a fixed type capacitor has a set capacitance value determined during manufacturing and cannot be adjusted. It serves as a reliable component for applications where specific capacitance is needed without alteration. A variable type capacitor, while adjustable, typically operates on a different principle—such as overlapping plates—rather than changing the distance between them. Lastly, an electrolytic capacitor is designed for a specific range of capacitance but does not allow for distance adjustment either, as it is polarized and optimized for stable operation at its rated capacitance.