Question

Which of the following transducers is most suitable for measuring very small displacements?

• A. LVDT
• B. Strain gauge
• C. Piezoelectric transducer
• D. Thermistor

Hint:

LVDTs are preferred for precision displacement measurement due to their high sensitivity, accuracy, and frictionless operation.

Answer 1

The Correct Option is A

To determine which transducer is most suitable for measuring very small displacements, let's analyze each option:

1. LVDT (Linear Variable Differential Transformer):
   • LVDTs are highly sensitive and accurate transducers used for measuring linear displacement, even in very small ranges.
   • They operate on the principle of mutual induction and provide output proportional to the displacement.
   • Due to their high sensitivity, good linearity, and low hysteresis, LVDTs are ideal for measuring minute displacements down to a few micrometers.
2. Strain Gauge:
   • Strain gauges measure strain (deformation) rather than direct displacement.
   • Though they can be used indirectly to measure displacement, they are not as direct or sensitive as LVDTs for small displacements.
3. Piezoelectric Transducer:
   • These transducers generate an electrical charge in response to mechanical stress.
   • They are more suited for measuring dynamic changes like vibrations, rather than static or very small displacements.
4. Thermistor:
   • Thermistors are temperature-sensing devices and are not suitable for displacement measurement.

Considering the functionality and sensitivity required for measuring very small displacements, the LVDT is the most appropriate choice among the given options.