Hey I have just begin my course with plant monitoring system.I am confused with the values i am getting.In my room i am getting the value of 1.02 thousand, while i was reading the other threads i found that it is the max value that LDR can measure.
Since the intensity of sunlight will be greater that this value then what is the use of monitoring if it will always show 1.02 thousand.
Moreover i also wanted to know why we used 10k ohms resistor and why we connected one end of resistor to A0 and other to ground.
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You can reduce the value of the resistance used to get fine readings.
There is no compulsion that you have to use a 10K ohm resistor you can use a resistor with different values. Try using a 1K ohm resistor.
We connect the resistor to ground and A0 in order to measure the voltage drop across the resistor with respect to ground.
We are not calculating the intensity of the light in the project, we are just mapping the voltage drop across the resistor to a number between 0-1023, which gives us a rough idea of the intensity and not the actual intensity of the light, if we want to calculate the intensity then there are certain calculations to be done which in turn depends on the value of the fixed resistor used.
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