Instrumentation Transducers

Electro Mechanical Transducers

Question 1
Marks : +2 | -2
Pass Ratio : 20%
Two phase induction motor can be used as AC tachometers.
True
False
Explanation:
One phase of the induction motor can be used to provide reference supply and the second phase can be used for providing output voltage related to speed.
Question 2
Marks : +2 | -2
Pass Ratio : 10%
Which of the following represents the expression of output from electromechanical flow meter?
BDV
BV
BD
BD2V
Explanation:
Output potential of electromechanical transducer will be equal to the product of magnetic flux density, diameter of pipe, and velocity of flow.
Question 3
Marks : +2 | -2
Pass Ratio : 10%
Which of the following quantities are sensitive to electromechanical flow meters?
Viscosity
Density
Temperature
None of the mentioned
Explanation:
Electromagnetic flow meters are insensitive to quantities like viscosity, density, and temperature of liquid etc.
Question 4
Marks : +2 | -2
Pass Ratio : 10%
Electromechanical system can be used for measuring vibration.
True
False
Explanation:
Electromechanical system can be used for measuring vibration, in which vibratory motion will be converted to an output voltage.
Question 5
Marks : +2 | -2
Pass Ratio : 10%
Which of the following can be measured using tachometers?
Angular speed
Linear speed
Acceleration
Vibration
Explanation:
Tachometers are special devices used to measure angular displacement of rotating shafts.
Question 6
Marks : +2 | -2
Pass Ratio : 20%
Which of the following is applicable for the electromagnetic flow meter?
It causes obstruction to flow
It doesn’t cause obstruction t flow
It cannot be used in slurries
None of the mentioned
Explanation:
Electromagnetic flow meters don’t cause obstruction to flow and can be used for measurement in slurries.
Question 7
Marks : +2 | -2
Pass Ratio : 30%
Which of the following is correct for the tachometer system?
First order system
Second order system
Third order system
Unpredictable
Explanation:
Tachometer systems are second order systems.
Question 8
Marks : +2 | -2
Pass Ratio : 10%
Electrodynamic vibration transducers are based on _____________
Magnetostriction
Electromagnetic induction
Self inductance
None of the mentioned
Explanation:
Electrodynamic vibration transducers are based on electromagnetic induction, in which magnet induces emf in a coil.
Question 9
Marks : +2 | -2
Pass Ratio : 10%
Which of the following is used for measuring emf between plates of transducers?
Low impedance voltmeter
High impedance voltmeter
Any voltmeter
None of the mentioned
Explanation:
High impedance voltmeters are used for eliminating the effect of drop due to the internal resistance of liquid measured.
Question 10
Marks : +2 | -2
Pass Ratio : 20%
Which of the following is correct for AC and DC tachometers?
Sensitivity if AC tachometer is very high
Sensitivity of DC tachometer is very high
Sensitivity of both are equal
None of the mentioned
Explanation:
For AC tachometer it has a sensitivity which is very less than the sensitivity of DC tachometers.