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Do All Thermocouples Have a Neutral Temperature? - Physics

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प्रश्न

Do all thermocouples have a neutral temperature?

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उत्तर

The temperature of the hot junction at which the thermo-emf in a thermocouple becomes maximum is called neutral temperature for that thermocouple. For a thermocouple in which the constants a and b have the same sign, the neutral temperature will be less than the temperature of the cold junction of the thermocouple \[\left(\text{as }\theta_n = - \frac{a}{b}\right).\]

There will be no neutral or inversion temperature, as the temperature of the hot junction cannot be less than the temperature of the cold junction.

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पाठ 11: Thermal and Chemical Effects of Current - Short Answers [पृष्ठ २१७]

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एचसी वर्मा Concepts of Physics Vol. 2 [English] Class 11 and 12
पाठ 11 Thermal and Chemical Effects of Current
Short Answers | Q 5 | पृष्ठ २१७

संबंधित प्रश्‍न

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Distinguish between emf and terminal voltage of a cell.


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A 10 V cell of negligible internal resistance is connected in parallel across a battery of emf 200 V and internal resistance 38 Ω as shown in the figure. Find the value of current in the circuit.


In a potentiometer arrangement for determining the emf of a cell, the balance point of the cell in open circuit is 350 cm. When a resistance of 9 Ω is used in the external circuit of the cell, the balance point shifts to 300 cm. Determine the internal resistance of the cell.


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Deduce the expressions for

(1) the equivalent e.m.f of the combination

(2) the equivalent resistance of the combination, and

(3) the potential difference between the point A and B.


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Answer the following question.

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