Instructions

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Lesson 11: Photo resistor
A photoresistor is a resistor whose resistance varies depending on the
incident light intensity. It is based on the photoelectric eect of
semiconductors. When the incident light is intense, the resistivity is
reduced. If the incident light is weak, the resistance increases. Photo r
esistors are normally used for light measurement, light control and
photovoltaic conversion (converting the change of light into a change of
electricity). They are used in various light control circuits for example as
optical switches. In this project this eect is used to adjust an LED to the
current light intensity.
For this is needed:
1x Mega2560 board
1x USB cable
1x Red M5 LED
1x 220 Ω resistor
1x 10 kΩ resistor
1x Photo resistor
1x Breadboard
5x Jumper cable