Nature of measurement signals: Is temperature variation typically treated as an analog quantity (continuous in value and time) prior to digitization in instrumentation and control systems?

Introduction / Context:
Physical phenomena such as temperature, pressure, and light intensity vary continuously. Sensors transduce these into electrical signals for monitoring and control. Whether a variable is analog or digital affects sensor choice, conditioning circuits, and the need for conversion.

Given Data / Assumptions:

• Temperature changes continuously in nature.
• Sensors (thermistors, RTDs, thermocouples, IC sensors) produce voltages/resistances that vary continuously with temperature.
• Digitization occurs only after analog front-end conditioning.

Concept / Approach:
An analog quantity is one that can assume any value within a continuous range. Temperature is fundamentally analog; the associated sensor output is an analog signal (e.g., RTD resistance vs °C, thermocouple voltage vs °C). To process digitally, an ADC is used to map the analog signal to discrete codes.

Step-by-Step Solution:

Verification / Alternative check:
Even when displayed as discrete numbers, the underlying phenomenon and sensor output remain analog until conversion. Oversampling and filtering improve measurement fidelity.

Why Other Options Are Wrong:
“Incorrect” denies the continuous nature of temperature. Sensor-specific caveats (RTD vs thermistor) do not change the analog characteristic.

Common Pitfalls:
Confusing digital readouts with digital sensors; even “digital temperature sensors” contain an internal ADC and deliver a digital interface.

Final Answer:
Correct