Objective
The objective of this activity was in order to gain an understanding of the relationship between voltage output and the light intensity of the solar cell, as well as the relationship between the wavelength of light and the voltage output of the solar cell.
Procedure
Before we go into the procedure lets focus on what we needed for this lab. The equipment needed included one solar cell, one voltage probe, a NXT adaptor, and one with a light source, Labview VI software, a ruler, colored film filters, and an excel sheet. Our group linearly increased the distance the light was from the solar panel by 2 centimeters starting with 0 centimeters. This distance is essential considering it is synonymous to the light intensity. This was the independent variable because it was the entity we were manipulating. The dependent variable was the voltage produced as a result of the light intensity. This comparison allowed us to put it into an excel sheet and find the average voltage per 10 seconds. After doing five trials starting with 0 centimeters, and ending with 8 centimeters, and finding the voltage average for each individual trial we graphed it. Now, let it be known that there were technical difficulties and our data did not produce any statistical significance; however, I will get into that more later.
After doing five trials we shifted to testing the different wavelengths of light and the voltage output. How did we do this? We don’t manipulate the distance or in other words its light intensity; however, we manipulated the colors. The colors represent different wavelengths because they are on different wavelengths. The colors we experimented with consisted of green, orange, white, and blue. Once again our data did not yield any statistical significance.
Results
| Light Intensity (Distance) | Voltage |
| 0 Centimeters | .513906 |
| 2 Centimeters | .6586525 |
| 4 Centimeters | .489343 |
| 6 Centimeters | .54799375 |
| 8 Centimeters | .48140333 |
| Colors | Voltage |
| Green | .66987975 |
| Orange | .66025625 |
| White | .6137475 |
| Blue | .6778975 |
Where Did We Go Wrong and What Should Have Happened?
The professor can attest to the fact that this was not a human error, but a technological one. For one portion we were utilizing a broken solar cell, and once we switched that out the computer started malfunctioning and not syncing with the software properly. We reconnected, and tried several different units by settling for data that legitimately did nothing for us. We didn’t even get the total of ten seconds when testing, but a range from seven to ten. Any experimenter knows how essential consistency is in a trial, and unfortunately we could not have it through no fault of our own.
But now what can I say about what should have happened? Well due to the fact that we talked about this in class I knew what was supposed to happen with the data regarding light intensity and voltage. Voltage decreases as distance increases, thus meaning voltage decreases as light intensity increases, which in other words means they have an inverse relationship. The relationship between wavelengths and voltage, after doing some research should place blue as the least, then followed by green, and then orange (ffden-2.phys.uaf.edu). Although our data produced held no statistical significance this elaborates on the concept that errors happen, and experiments go wrong. This is why it is essential to experiment several times due to the inability of realizing erroneous data in the midst of other experiments that yield similar results in respect to each other, but not one experimenter. Simply put, it happens and it is inevitable.
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