Question

Accelerometer is used for measurement of

• A. Speed
• B. Vibration
• C. Acceleration
• D. Force

Hint:

In machine condition monitoring, vibration velocity and displacement are often computed by integrating the acceleration signal from an accelerometer once and twice, respectively.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
An accelerometer is an electromechanical transducer designed to measure dynamic or static acceleration forces.
These forces can be static (like the continuous force of gravity) or dynamic (caused by movement, shock, or vibration).

Step 2: Detailed Explanation:
The fundamental physical quantity measured by an accelerometer is acceleration (rate of change of velocity over time).
Typically, it consists of a seismic mass suspended by a spring system inside a housing.
When subjected to acceleration, the seismic mass experiences a displacement relative to the housing, which is converted into an electrical signal (voltage or charge).
Depending on the sensor design, this conversion occurs via piezoelectric crystals, capacitive micro-structures (MEMS), or piezoresistive elements.
While accelerometers are heavily used in engineering to monitor machinery vibration (by analyzing high-frequency oscillatory acceleration), the direct, fundamental parameter measured by the device itself is acceleration.
For speed, a tachometer or speedometer is used.
For force, a load cell or dynamometer is used.

Step 3: Final Answer:
The fundamental physical quantity measured by an accelerometer is acceleration.