4.1 Key findings
From the data collected, it shows that Car Design 2 with a solar panel with a higher volt compared to Car Design 1, moves much faster than Car Design 1. It also shows that both car models would be slower under a lower light intensity compared to a higher one. For Car Design 1, it can travel the fastest with 100% of the solar panel exposed under the sun and the slowest it can move is when only 80% of the solar panel is exposed as for Car Design 2, it can travel the fastest with 100% of the solar panel exposed under the sun and the slowest it can move is when only 70% of the solar panel is exposed. Comparing both of the car models, both of them are similar in everything, the only difference is the volts in the solar panel.
When both solar panels are covered vertically by cardboard stripes of different percentage, both models of the toy car would not move however when covered horizontally by cardboard stripes of different percentage, the toy car would still function and the wheels would start moving.
4.2 Explanation of key findings
The explanation of Car Design 1 moving slower than Car Design 2 is because of the difference in volts. As stated before, Car Design 1 has a solar panel with a power of 2 volts while Car Design 2 has a solar panel with a power of 6 volts which can also be known as 3 times the power of Car Design 1. Since both solar panels were the same size, size of the solar panel would not affect the conclusion made in the experiment. Basically, Car Design 2 travelled faster than Car Design 1 as it has a higher volt in the solar panel compared to the other as the higher the volt of the solar panel, the higher the current would flow and the lower the resistance would be thus this results in our findings.
As for the speed of the toy cars, the toy cars would travel faster when it is under a higher light intensity; the higher the light intensity, the faster the car would travel, the lower the light intensity, the slower the toy car would travel. This is because the higher the light intensity, the more solar energy the solar panel would be able to absorb to convert into electricity to run the toy car thus this lets us know that our hypothesis of the toy car being able to move faster on its own under a higher light intensity compared to a lower light intensity is correct.
An explanation of the percentage the solar panel is exposed is that logically, the more the solar panel is exposed under the sun, the faster and more efficient it would work. Our results show that Car Design 1 could not move when more than 20% of the vehicle is covered while Car Design 2 could not move when more than 30% of the solar panel is not exposed to the sunlight. This findings show that the solar panel in Car Design 2 which has a higher volt, would be able to work better compared to the solar panel in Car Design 1 which has a lower volt. Despite the solar panel being covered more than 20% for Car Design 2, it was still able to work which shows that the higher voltage does affect how much the solar panel can work. With 6 volts and 30% of the solar panel covered, the solar panel was still able to function the toy car which means that the minimum percentage the solar panel needs to work is 70% while for Car Design 1 it needs at least 80% to function.
As for covering the solar panel horizontally and vertically, when the solar panel is covered vertically, it does not work. The true reason for that is unknown even though researching was done for many hours. Even though there was no answer, one of the hypothesis was that it was probably related to the way the solar panels work. If covered vertically, that might cause a short circuit due to what was underneath the glass of the solar panel. However when covered horizontally, the vehicle would function as by covering horizontally, this would cover the parts where solar energy is supposed to be absorbed thus the solar panel would still be able to function the solar powered toy car.
4.3 Evaluation of hypothesis
Our hypothesis was correct. We expected that the solar powered toy car would move faster with higher light intensity or higher exposed solar panel.
4.4 Areas for improvement
Areas of improvement includes the time management. Planning was a important factor in the experiment which was lacking during the entire research project. Also, more data collected would be an area we could improve on as we only took the timings for one run. If given another chance, we would take timings for three times just to ensure the results would be constant and relevant. Another area to improve would be our data collection. Due to lack of time management, the data collected was only the results of one run for each car design only one run when solar panel was covered and exposed less than 100%. If we were given another chance or more time, the team would have collected each data 3 times to ensure that the results were constant and reliable. The procedures could have been improved by simplifying and taking out a few steps that were unnecessary and could reduce the risks involve in the experiment.