RTD and Thermistor question

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claudiocamera

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I can't figure out how to solve the problem below. Any help ?

The response time of a Resistive Temperature Sensor (RTD) or a Thermistor NTC at ambient temperature changes when a constant current flows throught it. Show that the response time of a RTD increase while the response time of a NTC decreases.
 

I think, it is connected with the fact that power of RTD (caused by working current) is 10...100 times more than power of Thermistor. This power bring self heating of RTD and decreasing speed of heat transfer so increase responce time in comparison with Thermistor.
 

Unfortunatelly, it doesn't answer the question. According to your answer the RTD's response time would decrease and this is not what happens, it increases instead. Also, the RTDs and NTCs would have the same behaviour related with response time, just one more than other. Indeed they have opposite behaviour.

So , I would appreciate some help in show me directions on how to proove the statements below:

The response time of a Resistive Temperature Sensor (RTD) or a Thermistor NTC at ambient temperature changes when a constant current flows throught it. Show that the response time of a RTD increase while the response time of a NTC decreases.
 

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