What does the output of an accelerometer primarily represent?

The output of an accelerometer primarily represents the acceleration applied to the object. Accelerometers are designed to measure the rate of change of velocity of an object, which is the definition of acceleration. They capture the dynamic forces acting upon an object, converting these forces into a measurable electrical signal that corresponds to acceleration. This data is crucial for understanding the performance and behavior of vibrating systems, as it allows engineers and analysts to assess how rapidly the object is moving away from its rest position due to these forces.

In vibration analysis, acceleration data provides insights into the nature of the vibration, including its intensity and frequency characteristics. By measuring acceleration, one can derive other important parameters such as displacement and velocity, but the original signal is fundamentally an acceleration measurement. This is why option C is the most accurate representation of what an accelerometer outputs.