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A device to measure the intensity of light should I do. Help Please? Answered

Actually thisis ahomework.Wouldyou help me.Ido not know how.What materialsshould I use.I wonder how can I dol. In fact, my homework to make an the sensor, example of rain sensor. That is something like I will a new sensor produced. I'm sorry I'm trying to write Google translate

thanks.....

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The short-circuit-current of a solar cell should be roughly proportional to the intensity of light reaching the cell.

A simple model to explain how this works is to assume each single photon hitting the cell,  contributes one electron to the short circuit current.  Light intensity is (photons/time/area)*(area of cell) ~ (electrons/time) = current

As an example:  a silicon solar cell, with an area of about 1cm^2, illuminated with dim indoor lighting, produces a short-circuit-current of about 20 microamperes of direct current (DC).  The picture is from:
https://www.instructables.com/id/How-to-Listen-to-Light/#step5

20 microamperes (μA) is a  small amount of electric current, but easy enough for a typical, cheap, multimeter to measure.

In bright sunlight, this same setup would produce much more current.   I am guessing somewhere between 10 and 100 times as much current; i.e somewhere between 200 and 2000 μA, or 0.2 to 2.0 mA.

Anyway, the game here is that a solar cell can be used as a light sensor, where short-circuit-current is proportional to light intensity.