Question

Question about an electric circuit and calculating the volts

Answer 1

When the resistance of the thermistor is 200 ohms calculate the reading on the voltmeter. The correct answer is zero and the current in DCB is equal to 0.015A

Answer 2

Is it because the voltmeter measures potential difference and the current and the resistance (so the voltages) are exactly equal when the thermistor has resistance 200 ohms?

Answer 3

|@gleem You meditating on my question brah? :D

Answer 4

Actually sleeping. When the thermistor reaches 200 ohms both branches of the circuit DCB and DAB carry the same current. resistors with the same resistance and the same current have the same voltage drop. The voltage drop across DA is equal to DC. The voltage at D is fixed so the voltage at A is the same as C. you should be able to calculate the voltmeter reading for any thermistor resistance.

Answer 5

With all four resistors being equal the voltage drop across each resistor will be equal (3 volts). This means that the potential across the voltmeter is 0 because each terminal of the voltage is connected to points of equipotential.