Verified Solution • 2025–26 Session moderate

QPage 217: Q5: HC Verma: Concepts of Physics - Volume 2 Thermal and Chemical Effects of Electric Current Page 217: Q5 Solution: Do all thermocouples have a neutral temperature?

⚠️ Common Exam Traps & Conceptual Pitfalls

Students often assume the neutral temperature $\,\theta_n = -a/b\,$ is always a usable, positive value; they overlook that if the Seebeck coefficients $a$ and $b$ share the same sign, $\,\theta_n\,$ becomes negative and cannot be realized with a 0 °C reference. Always examine the signs of $a$ and $b$ before asserting the existence of a neutral temperature.

Do all thermocouples have a neutral temperature?

Step-by-Step Verified Solution

**Answer:** No, not all thermocouples have a neutral temperature. **Step-by-Step Explanation:** Neutral temperature is θn=−a/b\theta_n = -a/b. If constants aa and bb have the same sign, θn\theta_n is negative, meaning it lies below 0�C. Since the hot junction must be hotter than the cold junction (at 0�C), a negative neutral temperature is not achievable. Hence, no neutral temperature exists for such thermocouples [citation:12].

All Questions in this Chapter

QPage 217: Q1 QPage 217: Q2 QPage 217: Q3 QPage 217: Q4 QPage 217: Q5 QPage 217: Q6 QPage 217: Q7 QPage 217: Q8 QPage 217: Q9 QPage 218: Q1 QPage 218: Q2 QPage 218: Q3 QPage 218: Q4 QPage 218: Q5 QPages 217-218: Q1 QPages 217-218: Q2 QPages 217-218: Q3 QPages 217-218: Q4 QPages 217-218: Q5 QPages 217-218: Q6 QPages 217-218: Q7 QPages 217-218: Q8 QPages 218-219: Q1 QPages 218-219: Q2 QPages 218-219: Q3 QPages 218-219: Q4 QPages 218-219: Q5 QPages 218-219: Q6 QPages 218-219: Q7 QPages 218-219: Q8 QPages 218-219: Q9 QPages 218-219: Q10 QPages 218-219: Q11 QPages 218-219: Q12 QPages 218-219: Q13 QPages 218-219: Q14 QPages 218-219: Q15 QPages 218-219: Q16 QPages 218-219: Q17 QPages 218-219: Q18 QPages 218-219: Q19 QPages 218-219: Q20 QPages 218-219: Q21 QPages 218-219: Q22 QPages 218-219: Q23 QPages 218-219: Q24

Related Learning Resources & Exam Preparation

Chapter Practice Bank
Practice all topic-wise questions from Thermal and Chemical Effects of Electric Current
Reference Textbook Solutions
Explore complete chapter exercises for HC Verma: Concepts of Physics - Volume 2
Competitive PYQ Question Bank
Browse year-wise authentic previous years' questions with solutions
Authentic CBT Mock Tests
Simulate official exam environment with live timer and percentile scoring