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Thermistor Questions

Q3.The circuit shown below shows a thermistor connected in a circuit with two resistors, an ammeter and a battery of emf 15V and negligible internal resistance.

(a)     When the thermistor is at a certain temperature the current through the ammeter is 10.0 mA.

(i)      Calculate the pd across the 540 Ω resistor.

(1 mark)

(ii)     Calculate the pd across the 1200 Ω resistor.

(1 mark)

(iii)     Calculate the resistance of the parallel combination of the resistor and the thermistor.

(1 mark)

(iv)    Calculate the resistance of the thermistor.

(2 marks)

(b)     The temperature of the thermistor is increased so that its resistance decreases. State and explain what happens to the pd across the 1200 Ω resistor.

(3 marks)

(Total 9 marks)