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Figure 1 : A Circuit to illustrate a thermistor[1] Figure 2 : Relationship between Temperate and Resistance in
in thermistor[2]
From Figure 1 above, it can be noted that when the thermistor warms up as a result of heat from the hair dryer, resistance of the thermistor drops which result in current flowing from the 9v potential to the 0v, this current makes way to the base of transistor which lights up the led connected to it.[1]
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