The thermo emf of a thermocouple varies with the temperature θ of the hot junction as E = a θ + b θ 2 in volts where the ratio a / b is 70 0 ∘ C . If the cold junction is kept at 0 ∘ C , then the neut

Question

The thermo emf of a thermocouple varies with the temperature θ of the hot junction as E = a θ + b θ 2 in volts where the ratio a / b is 70 0 ∘ C . If the cold junction is kept at 0 ∘ C , then the neutral temperature is

TestHub · Accepted Answer

E = a θ + b θ 2 At neutral temperature dE / d θ = 0 ∴ d θ dE ​ = a + 2 b θ n ​ = 0 ; θ n ​ = − 2 b a ​ Now b a ​ = 70 0 ∘ C (given) θ n ​ = − 700/2 = − 35 0 ∘ C Now θ c ​ = 0 ∘ C . So, θ n ​ > 0 ∘ C But mathematically θ n ​ < 0 ∘ C .

Physics - Heat & Thermo Question with Solution | TestHub

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