Questions Paper GATE Instrumentation Engineering

Q1. If the A-matrix of the state space model of a SISO linear time Invariant system is rank deficient, the transfer function of the system must have

1. a pole with a positive real part
2. a pole with a positive real part
3. a pole with a positive imaginary part
4. a pole at the origin

Answer: D

Q2. Two systems with impulse responses h 1 (t) and h 2 (t) are connected in cascade. Then the overall impulse response of the cascaded system is given by

1. product of h 1 (t) and h 2 (t)
2. sum of h 1 (t) and h 2 (t)
3. Convolution of h 1 (t) and h 2 (t)
4. subtraction of h 1 (t) and h 2 (t)

Answer: C

Q3. The differential pressure transmitter of a flow using a venture tube reads 2.5 x 10 5 Pa for a flow rate of 0.5 m 3 /s. The approximate flow rate in m 3 /s for a differential pressure 0.9 x 10 5 Pa is

1. 0.30
2. 0.18
3. 0.83
4. 0.60

Answer: A

Q4. A bulb is a staircase has two switches one switch being at the ground floor and the other one at the first floor. The bulb can be turned ON and also can be turned OFF by any one of the switches irrespective of the state of the other switch. The logic of switching of the bulb resembles

1. an AND gate
2. an OR gate
3. an XOR gate
4. a NAND gate

Answer: C

Q5. An electrometer has input range of 0 to 10 g. natural frequency 30 Hz and mass 0.001 kg. The range of the secondary displacement transducer in mm required to cover the input range is

1. 0 to 2.76
2. 0 to 9.81
3. 0 to 11.20
4. 0 to 52.10

Answer: A

Q6. Signals from fifteen thermocouples are multiplexed and each one is sampled once per second with a 16-bit ADC the digital samples are converted by a parallel to serial converter to generate a serial PCM signal. This PCM signal is frequency modulated with FSK modulator with 1200 Hz as 1 and 960 Hz as 0.The minimum band allocation required for faithful re-production of the signal by the FSK receiver without considering noise is

1. 840 Hz to 1320 Hz
2. 960 Hz to 1200 Hz
3. 1080 Hz to 1320 Hz
4. 720 Hz to 1440 Hz

Answer: D

Q7. The thermal time constant of the hot wire under flowing air condition is ms is

1. 24.5
2. 12.25
3. 6.125
4. 3.0625

Answer: B

Q8. At steady state, the resistance of the wire in is

1. 10.000
2. 10.144
3. 12.152
4. 14.128

Answer: B

Q9. the minimum frequency of a force signal in Hz within its useful mid-band range of measurement, for which the gain amplitude is more than 095, approximately is,

1. 16
2. 160
3. 1600
4. 16 x 10 3

Answer: B

Q10. Statement : you can always give me a ring whenever you need Which one of the following is the best inference from the above statement?

1. Because I have a nice caller tune
2. Because I have a better telephone facility
3. Because a friend in need is a friend indeed
4. Because you need not pay towards the telephone bills when you give me a ring

Answer: C