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The following data pertains to the junction of a thermocouple wire used to measure the temperature of the gas stream. Density = 8500 kg/m3, specific heat = 325 J/kg K, thermal conductivity = 40 W/m K and the heat transfer coefficient between the junction and gas = 215 W/m2 K. If thermocouple junction can be approximated as 1 mm diameter sphere, determine how long it will take for the thermocouple to read 99% of the initial temperature difference

The following data pertains to the junction of a thermocouple wire used to measure the temperature of the gas stream. Density = 8500 kg/m3, specific heat = 325 J/kg K, thermal conductivity = 40 W/m K and the heat transfer coefficient between the junction and gas = 215 W/m2 K. If thermocouple junction can be approximated as 1 mm diameter sphere, determine how long it will take for the thermocouple to read 99% of the initial temperature difference Correct Answer 9.86 seconds

t – t a/t i – t a = exponential (- h A T/p V c).

Related Questions

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0.5 kg বরফকে 0°C থেকে 1000°C এ বাম্পে পরিণত করতে কত তাপ দরকার? [বাম্পীয় ভবনের সুপ্ততাপ  22.68×105 Jkg-1  , পানির সুপ্ততাপ 4.2×103 Jkg-1K-1 এবং বরঢ গলনের সুপ্ততাপ    33.4×104 Jkg-1  ]
বরফ গলনের আপেক্ষিক সুপ্ততাপের পরিমাণ-i. 36000 Jkg-1ii. 334000 Jkg -1iii. 336520 Jkg-1 নিচের কোনটি সঠিক?
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