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The time constant of a thermocouple is the time taken to

The time constant of a thermocouple is the time taken to Correct Answer Attain 63.2% of the value of the initial temperature difference

The time constant of a thermocouple represents the time required to attain 63.2% value.

Related Questions

A thermocouple junction in the form of 4 mm radius sphere is to be used to measure the temperature of a gas stream. The junction is initially at 35 degree Celsius and is placed in a gas stream which is at 300 degree Celsius. The thermocouple is removed from the hot gas stream after 10 seconds and kept in still air at 25 degree Celsius with convective coefficient 10 W/m2 K. Find out the time constant of the thermocouple. Assume the thermos-physical properties as given below h = 37.5 W/m2 K p = 7500 kg/m3 c = 400 J/kg K
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
In a survey of 25 students, it was found that 15 had taken Mathematics, 12 had taken Physics and 11 had taken Chemistry, 5 had taken Mathematics and Chemistry, 9 had taken Mathematics and Physics, 4 had taken Physics and Chemistry and 3 had taken all the three subjects. Find the number of students who had taken both Physics and Chemistry but not Mathematics.
In a survey of university students, 64 had taken Drama course, 94 had taken Dance course, 58 had taken a Singing course, 28 had taken Drama and singing course, 26 had taken Drama and dance course, 22 had taken Dance and singing course, and 14 had taken all the three courses. Find how many have taken only one course?
A thermocouple junction of spherical form is to be used to measure the temperature of the gas stream. The junction is at 20 degree Celsius and is placed in a gas stream which is at 200 degree Celsius. Make calculations for junction diameter needed for the thermocouple to have thermal time constant of one second. Assume the thermos-physical properties as given below k = 20 W/ m K h = 350 W/m2 K c = 0.4 k J/kg K p = 8000 kg/m3
A Time taken by pipe P and Q to fill the tank is 120/23 minutes. Time taken by drain pipe S to empty the tank is 12 minutes more than pipe P to fill the tank. Time taken by pipe Q is 15 minutes. Ratio of time taken by R to fill up the tank and by pipe Q is 4 : 5. What is total time taken to fill the whole tank when all the pipes are open? 
Time taken by pipe A and pipe B to fill up the cistern is 12 minutes whereas time taken by pipe C to empty the whole cistern is twice that of time taken by A and B together to fill the tank and ratio of time taken by pipe A and B to fill up the tank when operating alone is 2 : 3. If pipe A and B are alternatively opened every 6 minutes and C is opened with pipe B but closed when pipe A is opened then calculate total time taken to fill up the whole cistern. 
A can finish a work in half the time taken by B to finish the work. The time taken by C to finish the work is equal to the total time taken by A and B together to finish the work. What is the ratio of the time taken to finish the work when A, B and C work together to that of the time taken by A working alone?
“The response of a thermocouple is defined as the time required for the thermocouple to reach the surrounding temperature when it is exposed to it”.
The sensitivity of thermocouple is defined as the time required by thermocouple to reach how much percentage of its steady state values?