Lab 8: Solar Cell Experiment

In this experiment, we were asked to use a solar cell, a light, a ruler, and some colored gels to determine different aspects of light intensity. Specifically, we were asked to discover the relationship between the distance between the cell and a light source and light intensity, and also the color of light and how that effects intensity.

My partner and I started looking at the distance between our flashlight and our solar cell. Before we really began recording data, we tested the solar cell in the dark to determine its accuracy. We attempted to incorporate this data into our graph, but the data point made the trendline look as though it didn’t match at all so we removed it from our graph. We did get a small reading, but it was negligible. It was important for us to do this though, because after this step we were aware that our cell was not perfectly accurate. Luckily, it was still accurate enough that the experiment worked out for us.

To explore the relationship between distance between the cell and a light source and intensity, we took light intensity measurements at five different distances: 0cm, 3cm, 5cm, 7cm, and 9cm. Our measurements were recorded by the computer in intervals of ten seconds, and so we took the average of those recordings to get out data points. As is apparent from the graph, the farther away the light source is from the solar cell, the less intensity the cell records.

For the second half of the experiment, we used four different colored gels to look at how color has an impact on light intensity. We had red, blue, orange, and light pink, and of course white light without a gel. We took our measurements by holding the light source directly next to the solar cell with the gel in between, so distance would not be a factor in this experiment. Our findings were about what we expected: the darker the gel, the less intensity the solar cell will record. It was no surprise that white light gave the highest intensity, and the light pink one was not far behind. It also makes sense that orange and red came next, both because the orange was less opaque than the red and the blue, but because of the wavelengths of the colors. Red light has a much longer wavelength than blue light. The only thing that really surprised me about this experiment was that there wasn’t a more dramatic difference between the intensities of red and blue light, but I suppose that has something to do with the opacity of the gels. For a more perfect experiment, if I really wanted to look at how red light and blue light compare in terms of intensity, I would pick gels that all have the exact same amount of opacity.