GATE IN Sensor and Industrial Instrumentation PYQs & Answers

Questions 1–7 of 7. Imported answers require independent review unless marked reviewed.

The working of the hand-held metal detector most widely used by security personnel for human frisking is based on the principle of

Your answerChoose one option.

change in reluctance of an iron core in presence of a metallic object

change in conductance of an iron core in presence of a metallic object

electric field induced by a metallic object

eddy current generation in a metallic object

You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answer

The primary coil of a linear variable differential transformer (LVDT) is supplied with AC voltage as shown in the figure. The secondary coils are connected in series opposition and the output is measured using a true RMS voltmeter. The displacement

of the core is indicated in mm on a linear scale. At the null position

, the voltmeter reads 0 V. If the voltmeter reads 0.2 V for a displacement of

mm, then for a displacement of

mm, the voltmeter reading, in V, is

Diagram for Instrumentation Engineering question 14

Your answerChoose one option.

−0.3

−0.1

0.3

0.5

You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answer

In the force transducer shown in Figure (a), four identical strain gauges S1, S2, S3, and S4 are mounted on a cantilever at equal distance from its base. S1 and S2 are mounted on the top surface and S3 and S4 are mounted on the bottom surface, as shown in the Figure (a). These strain gauges are to be connected to form a Wheatstone bridge consisting of four arms A, B, C, and D, as shown in Figure (b). From the following options, the correct order to maximize the measurement sensitivity is

Diagram for Instrumentation Engineering question 15

Your answerChoose one option.

A → S1, B → S2, C → S4, D → S3

A → S1, B → S4, C → S3, D → S2

A → S1, B → S2, C → S3, D → S4

A → S1, B → S4, C → S2, D → S3

You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answer

Match the following sensors with their most suitable applications.

Sensor	Application
P Rotary Variable Differential Transformer	I Vacuum measurement
Q Thermocouple	II Force measurement
R Ionization Gauge	III Angular displacement measurement
S Strain Gauge	IV Temperature measurement

Your answerChoose one option.

P – II, Q – III, R – I, S – IV

P – I, Q – IV, R – II, S – III

P – III, Q – IV, R – II, S – I

P – III, Q – IV, R – I, S – II

You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answer

A metallic strain-gage (SG) with resistance

is connected as shown in the figure, where

represent the lead wire resistances. The SG has a gauge factor of 2 and nominal resistance

. When the SG is subjected to a tensile strain of

, the resulting change in

. The

value is measured as

. The

and

are the equivalent resistances measured between the terminals 1 and 2, and terminals 2 and 3, respectively.

, and

, the measured value of tensile strain is ___

(rounded off to two decimal places).

Diagram for Instrumentation Engineering question 53

You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answer

A schematic of a Michelson interferometer, used for the measurement of refractive index of gas, is shown in the figure. The transparent chamber is filled with a gas of refractive index

, where

, at atmospheric pressure. If a 532 nm laser beam produces 30 interference fringes on the screen, then the number of fringes produced by a 632.8 nm laser beam will be ____ (rounded off to one decimal place).

Note: Assume that the effect of beamsplitter width is negligible. The setup is placed in air medium with refractive index equal to 1.

Diagram for Instrumentation Engineering question 55

You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answer

The resistance of a thermistor is measured to be 2.25 kΩ at 30 °C and 1.17 kΩ at 60 °C. Its material constant

is __________ K (rounded off to two decimal places).

You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answer

GATE IN Sensor and Industrial Instrumentation PYQs

How to practice Sensor and Industrial Instrumentation

Question 13

Question 14

Question 15

Question 22

Question 53

Question 55

Question 58