What is a rate gyro primarily used to detect?

A rate gyro is a specific type of sensor that measures rotational motion or angular velocity. It operates based on the principles of angular momentum and is commonly used in inertial navigation systems, automotive stability control, and various aerospace applications. The primary function of a rate gyro is to detect changes in angular rates, which allows it to provide essential data about how fast an object is rotating around an axis.

This detection is crucial in systems where maintaining orientation and stability is necessary, such as in aircraft and spacecraft navigation. By providing continuous information about the rotational movement, the rate gyro enables effective control and adjustment to keep the system on its desired course or orientation.

In contrast, other options mention aspects not related to angular motion. Changes in speed pertain to linear motion rather than rotation, distance traveled focuses on displacement rather than rotation, and mass changes are unrelated to motion detection altogether. Hence, the capacity of a rate gyro to measure and report angular rates of change is its defining characteristic and primary purpose.