This experiment was used as an exercise so that we could understand how to use the different equipment to measure out the voltage output of the solar cell panel and the light intensity output of the NXT through Labview.
The materials/equipment that were needed in order to continue with this exercise included:
- One solar cell
- One voltage probe
- One NXT adaptor
- NXT with a light sensor
- One light source – flashlight
- Labview VI “solarlab1.vi” document
- Ruler
- Colored film filters
- Excel spreadsheet
Preparing for the exercise!
There are two parts to this experiment. The first part was to calculate the voltage output versus the light intensity. This was done by first recording the voltage without any light, then adding light onto the solar cell with no distance in between and increasing the distance from that. For this part of the experiment, my partner and I held the light source away from the solar cell 2 inches first, then 4 inches, 6 inches and finally 8 inches. With that data, we calculated the numbers from each distance and took the average voltage output according to the intensity of light the solar cell had.
The Excel Spreadsheet for 1st Collection of Data
As shown in the graph below, the further away the light source was from the solar cell, the lower the volt. Even though there was a minor change in the intensity of the light and whatnot, it is still shown in the graph that there were small increases with the changes in distance.
Graph of Average Voltage versus Intensity (distance)
The second part to this exercise was to use the color film filters. We went about the experiment for this part the same way we did for the first part except this time, we had three different colored film filters: pink, green, and yellow. For each time we calculated the voltage output, we would cover the solar cell with one of these colors. We first started without any filter, then pink, green and finally yellow. Our controlled variable for this part of the exercise was the intensity of the light. To do so, we kept the light source two inches above the solar cell for all the color changes. The point of using these film strips was to filter out certain colors (aka wavelengths). We would then be able to see the different voltages depending on the color changes and how they were each affected.
The graph below shows the different outcomes (averages) of the voltage output according to the color filters that were used. As seen, the pink filter allowed the most intensity to pass through the solar panel, followed by the yellow filter. Interestingly enough, having a green filter created lower outcomes than having no filter at all.
Graph of Average Voltage versus Filter Color
Great post and great pictures. I think you did a great job in explaining the in-class experiment for readers who aren’t a part of the class!