Measurement and Instrumentation Quiz: Pressure

Based on the "box" analogy provided in the text, what occurs when all molecules are completely removed from the box?

• The box reaches standard atmospheric pressure.

• The box reaches absolute zero pressure.

• The gauge pressure reaches its maximum value.

• The pressure becomes equivalent to barometric pressure.

If you are using a Bourdon tube device to measure the pressure of a car tire relative to the surrounding air, which type of pressure are you measuring?

• Absolute pressure

• Gauge pressure

• Differential vacuum pressure

• Total molecular pressure

What is another commonly used term for atmospheric pressure as mentioned in the text?

• Static pressure

• Hydrostatic pressure

• Barometric pressure

• Dynamic pressure

A Bourdon tube gauge with a range of 0 to 300 kPa has an accuracy of ±0.2% of full scale. What is the calculated uncertainty (accuracy error) in kPa?

• ±0.5 kPa

• ±0.6 kPa

• ±1.0 kPa

• ±1.5 kPa

The gauge reads +0.5 kPa when exposed to standard atmospheric pressure. What is this specific type of error called?

• Span error

• Hysteresis

• Zero error

• Linearity error

For a reading of 20 kPa with a total expected error of 1.1 kPa, what is the specific range in which the actual reading would fall?

• 20.0 kPa to 21.1 kPa

• 19.5 kPa to 20.5 kPa

• 18.9 kPa to 21.1 kPa

• 19.0 kPa to 20.0 kPa

How can an instrument engineer reduce the "zero error" found in a pressure measurement device?

• By replacing the entire gauge with a digital version

• By adjusting the zero screw or subtracting the offset from each reading

• By increasing the total pressure range of the system

• By changing the material of the sensing element

In a diaphragm pressure dial gauge, what is the primary sensing element?

• A gear and pinion mechanism

• A thin, flexible diaphragm

• A liquid-filled capillary tube

• An electronic strain gauge

What is the role of the "mechanical linkage" (transducer) in a diaphragm gauge?

• To convert the diaphragm's deformation into amplified needle movement

• To seal the process fluid away from the dial

• To measure the ambient temperature of the plant

• To provide the final pressure reading in units of electrical current

Which of the following represents the correct "signal flow" in the block diagram of a pressure gauge?

• Dial Indicator → Mechanical Linkage → Diaphragm → Process Variable

• Diaphragm → Process Variable → Mechanical Linkage → Dial Indicator

• Process Variable → Diaphragm → Mechanical Linkage → Dial Indicator

• Mechanical Linkage → Diaphragm → Dial Indicator → Process Variable