Process Control and Instrumentation

281. Which of the following is a desirable characteristic of an instrument?

1. High drift
2. High fidelity
3. High measuring lag
4. Poor reproducibility

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282. Which of the following is an undesirable dynamic characteristic of an instrument?

1. Reproducibility
2. Dead zone
3. Time lag
4. Static error

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283. Which of the following is never used as an element of industrial resistance thermometer?

1. Lead
2. Nickel
3. Copper
4. 30% iron + 70% nickel

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284. Which of the following is not a composition measuring instrument?

1. Thermal conductivity cell
2. Mass spectrometer
3. Polarograph
4. Hot wire anemometer

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285. Which of the following is not a differential pressure flow meter?

1. Rotameter
2. Flow nozzle
3. Orificemeter
4. Venturimeter

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286. Which of the following is not a mechanical pressure sensing element?

1. Bellows
2. Diaphragm
3. Bourdon tube
4. U-tube

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287. Which of the following is not a second order instrument?

1. Mercury in glass thermometer with covering
2. Bare mercury in glass thermometer
3. Pressure gauge with one bellow, two tubes and a tank
4. None of these

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288. Which of the following is not a variable area flow meter?

1. Piston type meter
2. Rotameter
3. Magnetic flow meter
4. Orifice and tapered plug meter

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289. Which of the following is not classified as a thermo electric pyrometer?

1. Resistance thermometer
2. Thermocouple
3. Optical pyrometer (disappearing filament type)
4. Radiation pyrometer

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290. Which of the following is not suitable for measuring the temperature of a red hot object in the range of 800 - 1600°C?

1. Optical pyrometer
2. Radiation pyrometer
3. Photoelectric pyrometer
4. Thermocouples

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