Exploring Piezoelectric Materials
The piezoelectric effect describes a material's ability to generate an electric charge when subjected to mechanical stress. It's a property typically found in non-centrosymmetric crystalline structures.
Analysis of Material Properties
- Quartz: A widely recognized piezoelectric material, commonly used in electronic oscillators and sensors due to its stable piezoelectric response.
- Barium titanate ($BaTiO_3$): A synthetic ceramic known for strong piezoelectric properties, making it suitable for transducers, actuators, and capacitors.
- Rochelle salt: One of the first substances discovered to exhibit piezoelectricity. While effective, its stability can be a limitation compared to other materials.
- Aluminum: A metal. Metals generally have centrosymmetric crystal lattices. This symmetry prevents the generation of a net polarization under stress, meaning they do not exhibit the piezoelectric effect.
Identifying the Non-Piezoelectric Option
Comparing the options, Quartz, Barium titanate ($BaTiO_3$), and Rochelle salt are confirmed piezoelectric materials.
Aluminum, due to its metallic nature and typically centrosymmetric crystal structure, does not exhibit the piezoelectric effect.
Therefore, Aluminum is the correct choice as it is NOT known for this property.
Important Questions from Sensors Transducers and Applications
Match List I with List II:
List I
(Transducer)
List II
(Application)
(A) Pirani gauge (I) Liquid level (B) Dielectric gage (II) Displacement (C) Magnetostriction gage (III) Gas flow (D) Variable capacitance pressure gage (IV) Sound Choose the correct answer from the options given below:
Arrange the following thermal sensors in ascending order of their cost for an application:
(A) Thermocouple
(B) Thermistor
(C) Resistance Temperature Detector (RTD)
(D) IR Photodiode
Choose the correct answer from the options given below:
Which of the following is not used as a security protocols
Which of the following is most commonly used IOT standards for Medium Access Control (MAC)
Match List I with List II:
List I
(Technologies for IOT)
List II
(Definitions)
(A) Sensors (I) Analytical tools that improve the ability to describe phenomenons (B) Networks (II) Commonly accepted prescriptions for action (C) Augmented intelligence (III) A device that generates an electronic signal from a physical condition (D) Standards (IV) A mechanism for communicating an electronic signal Choose the correct answer from the options given below:
