What component is part of a vertical speed indicator?

The vertical speed indicator (VSI) operates by measuring the rate of climb or descent of an aircraft, and the diaphragm is a crucial component of this instrument. Inside the VSI, the diaphragm is sensitive to changes in air pressure, which correlate with the aircraft's vertical movement. As the aircraft climbs or descends, the outside static pressure changes, causing the diaphragm to flex. This flexing action is then translated into a reading on the VSI, indicating whether the aircraft is ascending or descending and at what rate.

Other components such as electrical sensors, pressure relief valves, and temperature sensors do not fulfill the primary function of a vertical speed indicator. While sensors and valves are important for other types of instrumentation or aircraft systems, they do not play a role in the basic operation of the VSI, which relies heavily on the mechanical properties of the diaphragm to provide accurate vertical speed readings.