Current through voltmeter and ammeter

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SUMMARY

The discussion centers on the behavior of a thermistor in a circuit with an ideal voltmeter and ammeter. As temperature decreases, the resistance of the thermistor increases, leading to a decrease in current due to Ohm's Law (V=IR). Participants clarify that while the total resistance increases, the voltmeter measures the voltage across the thermistor, which remains unaffected by the current through an ideal voltmeter. The correct answer to the posed question is option A, emphasizing the importance of understanding ideal circuit components.

PREREQUISITES
  • Understanding of Ohm's Law (V=IR)
  • Knowledge of thermistor behavior and characteristics
  • Familiarity with ideal circuit components (ideal voltmeter and ammeter)
  • Basic concepts of electrical circuits and resistance
NEXT STEPS
  • Study the characteristics and applications of thermistors in circuits
  • Learn about the implications of using ideal versus real voltmeters and ammeters
  • Explore advanced circuit analysis techniques involving resistive components
  • Investigate the effects of temperature on resistance in various materials
USEFUL FOR

Electrical engineering students, circuit designers, and anyone interested in understanding the principles of circuit analysis involving thermistors and ideal measuring instruments.

ravsterphysics
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3. The Attempt at a Solution

As temp decreases, the resistance of the thermistor increases...doesn't this mean that the voltmeter will increase too since V=IR?

I know that the total resistance of the circuit has increased so less current, but I put down option D but the correct answer is A?
 
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Suppose that the voltmeter and ammeter are ideal and the cell has emf V. If at some moment the thermistor has a resistance R, what voltage would the voltmeter measure across R?
 
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Likes   Reactions: Albert Thomas
There's never any current through an ideal voltmeter, and never any voltage drop through an ideal ammeter.
 

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