Q121 / 200 · NEET 2011 (Screening) · Physics

The rate of increase of thermo-emf with temperature at the neutral temperature of a thermocouple

  • Correct answer
    A
    is zero
  • B
    depends upon the choice of the two materials of the thermocouple
  • C
    is negative
  • D
    is positive

Solution

We have $$ e=a t+b t^2 $$ Natural temperature $\frac{d e}{d t}=a+2 b t$ $$ T_n=-\frac{a}{2 b} $$ At netural temperature $$ \frac{d e}{d t}=0 $$

Hence, the correct answer is option: 'A'.

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