Current Electricity: Calculating Power at 0 & 100 Degrees C

AI Thread Summary
The discussion focuses on calculating power dissipated in a thermistor at two temperatures: 100°C and 0°C. At 100°C, the resistance is 60k ohms, and at 0°C, it is 100k ohms, with a series resistor of 12k ohms. The user correctly calculated power at 100°C but encountered issues with the calculation at 0°C, resulting in an incorrect answer. The suggested approach involves finding total resistance, calculating total current, and then using the formula P = I^2 R for power dissipation. The correct answer for power at 0°C is noted to be 4 microwatts.
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I am revising the chapter on current electricity and i came across this question which i got stuck in the last part. It shows a circuit with a thermistor having a resistane of 60k ohms at 100 deg C and 100k ohm at 0 deg C. The termistor is in series witha 12 k ohm resistor There is a voltmeter but we are told that we can consider it behaving ideally. Now the last questions were: depermine the power dissipated in the thermistor at
a 100 deg C
b 0 deg C

Checking my answer for a , it was worked out rigght :). but d problem is b, i got a wrong ans when I used the same method ie

I found R total by adding the 2 resistances. Then using ratios I found voltage across the thermistor which is 10.7, then using I=V/R i found I and then used P=IV. What is wrong pls? My book says that the ans is 4microwatts
 
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You are most likely using the wrong value for voltage or current at some stage. If you could write out your calculations.

One method in doing the problem is to find the total resistance, then find the total current. To find the power dissipating through any resistor, then use P_1 = I^2 R_1.
 
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