85. The orsat apparatus is used for measuring:
A.Chemical analysis of flue gases
B.Moisture in air
C.Composition of alloys
D.Colour spectrum

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86. The error caused in vibration measuring equipment due to non compliance (not stiff) of bond made between sensor and the surface it is mounted is called :
A.Cross-coupling
B.Coupling compliance
C.Influence error
D.Subject loading by sensor

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87. Machine health monitoring is mainly based on measurement of :
A.Lub oil pressure
B.Vibrations at strategic points
C.Bearing temperature measurement
D.Efficiency and losses of machine

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88. Mass-spring seismic sensors measure directly the :
A.Displacement
B.Velocity
C.Acceleration
D.Shock

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89. An operation which, in the presence of a disturbing influence, tends to reduce the difference between the actual state of a system and an arbitrarily varied desired state and which does so on the basis of this difference, is called :
A.Automatic control
B.Feedback control
C.Open feed back control
D.Closed feed back control

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90. An apparatus which measures the value of a quantity or condition which is subject to change with time, and operates to maintain within limits this measured value, is called
A.Automatic regulator
B.Self controller
C.Feedback controller
D.Two-position controller

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91. The time required for the controlled variable to reach a specified value after the application of a step input is called
A.Rise time
B.Settling time
C.Response time
D.Peak time

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