IGCSE Physics Online Class

Here is one of the question from IGCSE Physics Paper. In the exam question, student should understand the basic diagram of thermocouple and how it function. Since the question uses the measurement object as sulphur, make sure you indicate that you deduce the measurement with the object sulphur

 

How a Thermocouple Works:

1. Two Different Metals: A thermocouple consists of two dissimilar metal wires (e.g., copper and constantan, or iron and chromel) joined at two points—hot junction and cold junction.
2. Temperature Difference: When the hot junction is exposed to a different temperature than the cold junction, a voltage is produced due to the Seebeck effect.
3. Voltage Measurement: The voltage generated is small (in millivolts) but can be measured with a device like a voltmeter or a thermocouple reader.
4. Conversion to Temperature: The measured voltage is converted into temperature using standard thermocouple reference tables or formulas.

Key Features of a Thermocouple:

• Fast response time
• Wide temperature range (depending on the type)
• No external power required
• Durable and can work in harsh environments