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LO: Describe the action of thermistors and light- dependent resistors and show understanding of their use as input transducers. LDR ’ s and Thermistors. Starter: use Pg 206-211 to complete the table. Variable Resistor. Thermistor.
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LO: Describe the action of thermistors and light- dependent resistors and show understanding of their use as input transducers LDR’s and Thermistors Starter: use Pg 206-211 to complete the table Variable Resistor Thermistor Can you think of any electrical devices which turn on without a switch?
Light dependant resistor – resistance DECREASES when light intensity INCREASES Resistance Amount of light Street lamps use LDR’s so they know when to switch on and off Digital cameras use LDR’s to control the amount of light which is allowed in
Resistance Temperature Thermistor – resistance DECREASES when temperature INCREASES Used in central heating timers