Which of the following devices is used to measure the highest temperature range?

Explanation:

Measurement of the Highest Temperature Range

Definition: The measurement of temperature in various industrial and scientific applications requires specific devices that are designed to operate within particular temperature ranges. The highest temperature ranges can only be measured by devices that are constructed to withstand extreme heat while maintaining accuracy and reliability. Among the listed options, the device that can measure the highest temperature range is the Noble Metal Thermocouple.

Correct Option Analysis:

The correct answer is:

Option 2: Noble Metal Thermocouple

Noble Metal Thermocouple: Noble metal thermocouples are made using noble metals such as platinum and rhodium. These thermocouples are specifically designed to measure high temperatures, often up to 1800°C or more. Some of the most commonly used noble metal thermocouples are Type R, Type S, and Type B thermocouples.

Key Features of Noble Metal Thermocouples:

• Material Composition: They are made from a combination of noble metals like platinum and rhodium, which are highly resistant to oxidation and corrosion at elevated temperatures.
• High-Temperature Range: Noble metal thermocouples can measure temperatures up to approximately 1800°C, making them suitable for applications like metal smelting, glass manufacturing, and high-temperature furnaces.
• Accuracy and Stability: These thermocouples offer excellent accuracy and stability over a wide temperature range, ensuring reliable readings even in extreme conditions.

Applications of Noble Metal Thermocouples:

• Used in industries such as metal processing, ceramics, and glass manufacturing, where extremely high temperatures are present.
• Found in laboratories and research facilities for precise high-temperature measurements.
• Commonly used in aerospace and power generation industries to monitor turbine and exhaust temperatures.

The noble metal thermocouple is the most suitable device for measuring the highest temperature range due to its unique combination of material properties, accuracy, and ability to withstand extreme environments.

Additional Information

To further understand the analysis, let’s evaluate the other options:

Option 1: Base Metal Thermocouple

Base metal thermocouples, such as Type K, J, T, and E, are constructed from less expensive metals like nickel and copper. These thermocouples are widely used in industrial applications for temperature measurements up to around 1000°C. While they are cost-effective and versatile, they cannot measure the extremely high temperatures that noble metal thermocouples can handle. Therefore, this option is not suitable for measuring the highest temperature range.

Option 3: Resistance Thermometer

Resistance thermometers, also known as Resistance Temperature Detectors (RTDs), measure temperature by correlating the resistance of a material (usually platinum) with temperature. These devices are highly accurate and stable but are generally limited to a temperature range of approximately -200°C to 850°C. Due to this limitation, resistance thermometers are not suitable for measuring the highest temperature ranges.

Option 4: Platinum Resistance Thermometer

Platinum resistance thermometers are a specific type of RTD that use platinum as the sensing element. They offer excellent accuracy and stability and are commonly used in laboratory and industrial applications. However, their temperature range is typically limited to around -200°C to 850°C, similar to standard RTDs. As a result, they are not capable of measuring the extremely high temperatures that noble metal thermocouples can handle.

Conclusion:

The correct choice for measuring the highest temperature range is the Noble Metal Thermocouple (Option 2). These thermocouples are specifically designed for extreme temperature conditions and are widely used in industries requiring precise high-temperature measurements. While other devices like base metal thermocouples, resistance thermometers, and platinum resistance thermometers have their unique advantages, they are not suitable for the highest temperature ranges, making noble metal thermocouples the optimal choice.