Question

A thermocouple ammeter/voltmeter has ___
1. A logarithmic law response
2. A square law response
3. A linear law response
4. None of these

Answer 1

Correct Answer - Option 2 : A square law response

• If the scale is directly proportional to the quantity being measured, then it follows the uniform law
• If the scale is directly proportional to the square of the quantity being measured, then it follows the square law
• If an instrument has a cramped scale for larger values, then it follows logarithmic law; In this case, the instrument instruments will have a wide range
• In a thermocouple ammeter/voltmeter, the scale is directly proportional to the square of the current and hence it has square law response.