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10 Cards in this Set
- Front
- Back
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What is an LDR?
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An LDR is a component that has a (variable) resistance that changes with the light intensity that falls upon it. This allows them to be used in light sensing circuits. It is a resistor.
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LDR's change depending on what the conditions are, what are they?
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1. In bright light, the resistance falls 2. In darkness, the resistance is highest |
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How are LDR'S useful?
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The conditions makes it a useful device for various electronic circuits e.g. automatic night lights and burglar detectors
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What does LDR stand for ?
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Light Dependent Resistor
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What is a thermistor?
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An electrical resistor whose resistance is greatly reduced by heating, used for measurement and control.
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Thermistors change depending on what the conditions are, what are they?
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1. In hot conditions, the resistance drops 2. In cool conditions, the resistance goes up |
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What are thermistors good at?
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They are useful temperature sensors e.g. car engine temperature gauges and electronic thermostats
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Using a thermistor and a fixed resistor in a potential divider, what can you make?
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A temperature sensor that gives a high voltage output when its hot and a low output when its cold.
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What does a thermistor graph look like ? |
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What does a LDR graph look like ? |
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