A 6.0 V battery is connected to a 40 Ω resistor and a thermistor, connected in series with each other. A voltmeter is connected across the 40 Ω resistor.
At 20 ∘C20\ ^\circ\text{C}20 ∘C the resistance of the thermistor is 80 Ω. Calculate the reading on the voltmeter at 20 ∘C20\ ^\circ\text{C}20 ∘C. Use the equation: potential difference=current×resistance\text{potential difference} = \text{current} \times \text{resistance}potential difference=current×resistance
The temperature of the thermistor is increased to 60 ∘C60\ ^\circ\text{C}60 ∘C. Explain the effect on the reading on the voltmeter.
Give one use of a circuit like this one.