By measuring the voltage across the LDR using a multimeter, you can infer light intensity: higher voltage readings correspond to lower light, while lower voltages indicate stronger light. The term "intensity" is used in different ways, so take a moment to learn what units and measuring methods match your goals. It is a measure of the brightness or strength of light in a specific location and is typically expressed in units such as lux (lumens per square meter) or foot-candles. To perform these measurements, technicians often use lux meters to measure the intensity of. How Does the Intensity of Light Change with Distance? Set up your multimeter to measure the resistance of the photoresistor, as shown in Figure 2. Plug the black multimeter probe into the port labeled COM. The voltmeter can be from your existing multimeter.
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