Match the following lists : Choose the correct answer from the codes given below:List – I List – II a. Electromechanical Device i. Seismic Device b. Optical Device ii. Piezo-electric c. Gyroscopic device iii. Interferometers d. Absolute motion device iv. Aerospace vehicle
a-ii, b-iii, c-iv, d-i
Each entry in List I names a class of measuring device and List II gives the example or application that belongs to it.
a → ii. Electromechanical device — piezo-electric. A piezoelectric crystal converts mechanical stress directly into electric charge (and the reverse), so it is the archetypal electromechanical transducer:
\(Q=d\,F\)
with d the charge sensitivity of the material. Being self-generating and extremely stiff, it responds to very fast events, which is why it is used in accelerometers, force and pressure sensors and ultrasonic transducers.
b → iii. Optical device — interferometers. An interferometer measures displacement by counting the fringes formed when a reflected beam interferes with a reference beam, each fringe corresponding to a movement of λ/2. Since the wavelength of light is the yardstick, resolution reaches nanometres — the standard for length metrology and precision machine-tool calibration.
c → iv. Gyroscopic device — aerospace vehicle. A gyroscope resists change of its spin-axis orientation and precesses under an applied torque, so it provides an inertial reference direction without any external signal. That is exactly what an aircraft, missile or spacecraft needs for attitude reference and inertial navigation.
d → i. Absolute motion device — seismic device. Measuring motion normally needs a fixed reference to measure against, which is unavailable on a moving vehicle or a shaking structure. A seismic instrument solves this by carrying its own reference: a spring-mounted mass inside the case, whose inertia keeps it nearly stationary in space while the case moves with the object. The relative displacement between mass and case then gives the absolute motion of the object. Above its natural frequency the same instrument reads displacement (a vibrometer) and below it reads acceleration (an accelerometer).
The quick route: pair "piezo-electric" with electromechanical and "interferometers" with optical — both are self-evident — then the aerospace application clearly belongs to the gyroscope, leaving the seismic mass as the absolute-motion device.
Hence, the correct matching is a-ii, b-iii, c-iv, d-i.
Similar Questions
Which of the following statements are correct ?
A. Hygrometer measures the value of humidity directly
B. Hygrometer measures the value of humidity indirectly
C. Wien's bridge is used to measure the frequency of the signal
D. Wien's bridge is used to measure the amplitude of the signal
E. Bimetallic strip is a thermal expansion detector.
Choose the most appropriate answer from the options given below :
Which of the following statements are correct
A. Megnetostrictive transducer operation depends on the change of permeability of magnetic material is when strained.
B. Potentiometer is an active transducer.
C. Turbine flow meters are volumetric flow meters
D. Any metal can be thermistor.
E. Thermocouples are used in high accuracy measurements.
Choose the most appropriate answer from the options given below :
Match List I with List II
LIST I LIST II A. Stroboscope I. Changes its electrical resistance with temperature B. Bolometer II. Generate thermoelectric emf C. Thermocouple III. Changes pressure to displacement D. Diaphragm IV. For measurement of rotary motion Choose the correct answer from the options given below:
Consider the following transducers or transducer systems :
(a) Float elements
(b) Seismic system
(c) Gyroscope
Arrange the above transducers/systems in decreasing order of the availability of possible number of output signals.
Consider the following statements associated with electrical and electronic transducers
A. Little power is consumed by transducer
B. Mass intertia effects are not minimized
C. The response time is small
D. Transmission and processing the signal for the purpose of measurement are easier.
Choose the correct answer from the options given below:
Match List I with List II
LIST I LIST II A. Relative error I. The ability of tde device to give identical O/P when repeated measurements are made witd tde same I/P signal B. Precision II. The ratio of difference between measured value and tde true value to tde true value of tde measurand C. Caliberation III. The smallest increment in measure tdat can be detected witd certainity by tde instrument D. Resolution IV. The process of making adjustments or tde scale so tdat tde instrument reading conform to an accepted standard. Choose the correct answer from the options given below:
The fundamental law that is used in temperature measurement is known as
Assertion (A) : Normally, some standard signal conditioner and display devices are used with a transducer, unless they are custom-built to suit the requirements of the transducers.
Reason (R) : A transducer is a device which receives energy in one form and transfer it to a convenient form.
Select your answer using the codes given below :
Which of the following transducers are not linear ?
i. thermistor
ii. thermocouple
iii. IC sensorWhich of the following sensors has excellent linearity ?
Important Questions from Basics of Transducers
Which of the following can act as an inverse transducer?
For transducers, following statements are given:
(A) An optical interferometer is useful for measuring extremely small motions
(B) The damping ratio of a seismic instrument should be low for good dynamic performance
(C) A rate gyro is a relative motion measuring device
(D) A pneumatic motion transducer is non-linear over a wide range of motion
(E) A piezoelectric accelerometer can only be used for static motion measurement
Choose the correct answer from the options given below:
Choose the INCORRECT statement with respect to the use of electrical transducers.
Consider the following transducers:
1. LVDT
2. Piezoelectric
3. Thermocouple
4. Photovoltaic cell
5. Strain gauge
Which of these are active transducers?
Under which condition, Transducers must operate?
