1. Which of the following is not a primary process variable?
(A) Flow
(B) Pressure
(C) Temperature
(D) Resistance
2. Flow, pressure, temperature, and level are collectively known as:
(A) Control actions
(B) Process variables
(C) Final control elements
(D) Signal conditioners
3. The flow of a fluid is defined as:
(A) The amount of fluid passing through a point per unit time
(B) The pressure of the fluid
(C) The velocity only
(D) The density of the fluid
4. The SI unit of volumetric flow rate is:
(A) m/s
(B) m³/s
(C) kg/s
(D) N·m
5. A rotameter is used to measure:
(A) Temperature
(B) Flow rate
(C) Pressure
(D) Level
6. A venturi meter works on the principle of:
(A) Temperature change
(B) Bernoulli’s theorem
(C) Boyle’s law
(D) Pascal’s law
7. The orifice plate is used for measuring:
(A) Flow
(B) Temperature
(C) Level
(D) Pressure
8. A Pitot tube measures:
(A) Static pressure
(B) Dynamic pressure and flow velocity
(C) Temperature
(D) Level difference
9. The differential pressure transmitter in a flow meter measures:
(A) Temperature difference
(B) Pressure difference across the restriction
(C) Flow direction
(D) Flow noise
10. The pressure of a fluid is defined as:
(A) Force per unit area
(B) Energy per unit mass
(C) Volume per unit time
(D) Force times distance
11. The SI unit of pressure is:
(A) Pascal (Pa)
(B) Bar
(C) Torr
(D) psi
12. The Bourdon tube is commonly used to measure:
(A) Flow
(B) Temperature
(C) Pressure
(D) Level
13. The manometer is based on the principle of:
(A) Liquid column balance
(B) Thermal expansion
(C) Electromagnetic induction
(D) Sound resonance
14. The piezoelectric transducer is used for measuring:
(A) Static pressure only
(B) Dynamic pressure
(C) Fluid level
(D) Flow velocity
15. Temperature is a measure of:
(A) Pressure of a system
(B) Average kinetic energy of molecules
(C) Flow rate
(D) Viscosity
16. The SI unit of temperature is:
(A) Celsius
(B) Fahrenheit
(C) Kelvin
(D) Rankine
17. A thermocouple works on the principle of:
(A) Seebeck effect
(B) Piezoelectric effect
(C) Photoelectric effect
(D) Induction principle
18. An RTD (Resistance Temperature Detector) measures temperature by:
(A) Change in resistance with temperature
(B) Change in capacitance
(C) Change in inductance
(D) Change in frequency
19. A thermistor is made of:
(A) Metal
(B) Semiconductor material
(C) Ceramic
(D) Plastic
20. The thermistor has a:
(A) Positive temperature coefficient of resistance
(B) Negative temperature coefficient of resistance
(C) Constant resistance
(D) Zero temperature sensitivity
21. The temperature transmitter converts temperature signals into:
(A) Standard electrical output (e.g., 4–20 mA)
(B) Pneumatic output
(C) Mechanical motion
(D) Thermal expansion
22. The level of a liquid in a tank can be measured using:
(A) Float and displacer
(B) Thermocouple
(C) Strain gauge
(D) Tachometer
23. A differential pressure level transmitter works on the principle that:
(A) Pressure difference corresponds to liquid height
(B) Flow rate is proportional to pressure
(C) Level affects temperature
(D) Pressure remains constant
24. The ultrasonic level sensor works on:
(A) Reflection of sound waves
(B) Thermal expansion
(C) Optical reflection
(D) Mechanical rotation
25. The capacitance-type level sensor works based on:
(A) Change in capacitance with level variation
(B) Change in resistance
(C) Change in inductance
(D) Vibration
26. The sight glass is used to:
(A) Visually monitor liquid level
(B) Measure pressure
(C) Indicate flow direction
(D) Record temperature
27. The float-type level indicator is suitable for:
(A) Solids only
(B) Liquids only
(C) Gases
(D) Vacuum systems
28. The turbine flow meter is used to measure:
(A) Flow rate
(B) Level
(C) Temperature
(D) Pressure
29. The Coriolis flow meter measures:
(A) Mass flow rate
(B) Volumetric flow rate
(C) Static pressure
(D) Temperature
30. The magnetic flow meter requires the fluid to be:
(A) Non-conductive
(B) Electrically conductive
(C) Transparent
(D) Compressible
31. The V-notch weir is used to measure:
(A) Flow of liquids in open channels
(B) Gas pressure
(C) Temperature of steam
(D) Level in closed tanks
32. The pressure transmitter output is typically:
(A) 4–20 mA
(B) 0–5 V
(C) 10–90 psi
(D) 0–10 V
33. The gauge pressure is measured relative to:
(A) Absolute vacuum
(B) Atmospheric pressure
(C) Standard temperature
(D) Reference voltage
34. The absolute pressure is measured relative to:
(A) Perfect vacuum
(B) Atmospheric pressure
(C) System pressure
(D) Standard air column
35. The differential pressure is:
(A) Difference between two pressures
(B) Sum of two pressures
(C) Absolute pressure
(D) Static pressure
36. The temperature range of a thermocouple depends on:
(A) Type of materials used
(B) Wire length
(C) Magnetic field
(D) Pressure
37. The level transmitter in pressurized vessels must use:
(A) Differential pressure measurement
(B) Float sensor
(C) Ultrasonic sensor only
(D) Capacitance probe
38. The vapor pressure of a liquid increases with:
(A) Decrease in temperature
(B) Increase in temperature
(C) Constant temperature
(D) Change in density
39. Flow rate in a pipeline can be increased by:
(A) Increasing pressure difference
(B) Increasing pipe friction
(C) Reducing pump power
(D) Reducing fluid density
40. The accuracy of process variable measurement mainly depends on:
(A) Calibration and sensor quality
(B) Pipe size
(C) Liquid color
(D) Voltage supply