I have problems with this problem I can't seem to figure it out I have attached the diagram so hopefully someone can help me. here is what the problem says:
This is simple temperature monitoring circuit. As the temperature of the liquid increases in the tank changes, so the resistance of the thermistor. This will change current through it, and also the current through the 10 ohm resistor Rx. The voltmeter which is calibrated directly in degrees centigrade will measure this. If the circuit is to be accurate we must have a constant voltage across A and B. Therefore we use a zener diode. At 0 degrees C the voltage drop across Rx is .125 volt. What is the resistance of the thermistor ?
the instructor gives a hint has This si circuit with 10V across A and B and Rx and T in a series if Rx drops .125V what is the drop across T ? Then find I and Rt
that hint really messed me up. so I am totally lost. thanks for any useful help.
sorry about the bad drawing it the was best I could on such short notice. I got to figure this out by Monday.
This is simple temperature monitoring circuit. As the temperature of the liquid increases in the tank changes, so the resistance of the thermistor. This will change current through it, and also the current through the 10 ohm resistor Rx. The voltmeter which is calibrated directly in degrees centigrade will measure this. If the circuit is to be accurate we must have a constant voltage across A and B. Therefore we use a zener diode. At 0 degrees C the voltage drop across Rx is .125 volt. What is the resistance of the thermistor ?
the instructor gives a hint has This si circuit with 10V across A and B and Rx and T in a series if Rx drops .125V what is the drop across T ? Then find I and Rt
that hint really messed me up. so I am totally lost. thanks for any useful help.
sorry about the bad drawing it the was best I could on such short notice. I got to figure this out by Monday.
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