Process Control and Instrumentation

61. Dilatometer is used to measure

1. Stress
2. Strain
3. Deflection
4. Contraction/expansion due to changes in temperature

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62. Dilute wine was used as a thermometric liquid initially to develop temperature scale. First empirical temperature scale developed was the _________ scale.

1. Kelvin
2. Centigrade
3. Fahrenheit
4. Reaumer

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63. Dome temperature of blast furnace stove is most accurately measured by a

1. Radiation pyrometer
2. platinum-platinum/rhodium thermocouple
3. Iron-constantan thermocouple
4. Platinum resistance thermometer

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64. E.m.f. generated by thermocouples is of the order of

1. Milli volts
2. Micro volts
3. Volts
4. Kilo volts

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65. Emf developed by a thermocouple while measuring a temperature of 400°C is 22 mV. The type of thermocouple used is

1. Chromel-alumel
2. Iron-constantan
3. Platinum-rhodium
4. Platinum-platinum + rhodium

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66. Emf developed by a thermocouple while measuring a temperature of 800°C is about 31 mV. The type of thermocouple used is

1. Chromel-alumel
2. Iron-constantan
3. Platinum-platinum + rhodium
4. None of these

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67. Emf developed by a thermocouple, while measuring a temperature of 600°C is about 5.5 mV. The type of thermocouple used is

1. Chromel-alumel
2. Iron-constantan
3. Platinum-platinum + rhodium
4. Either (A), (B) or (C)

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68. Emf generated in a thermocouple depends on the temperature

1. Of cold junction only
2. Of hot junction only
3. Difference between hot and cold junctions
4. Difference between cold junction and atmospheric temperature

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69. Emission spectroscopy is used for

1. Solids and metal analysis
2. Determining water purity
3. Determination of CO₂ in gases
4. NOx determination

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70. Feed forward controller accounts for the _________ changes.

1. Set point
2. Load
3. Both (A) & (B)
4. Neither (A) nor (B)

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