This past class was spent discovering ways to generate electricity-using flashlights as generators. Magnets were located inside the flashlight that would move through a magnetic field when being shaken up and down, thereby causing a change in the field, which produced electricity! A simple shake of the wrist garnered enough change to power the flashlight, but after trial and error my partner and I discovered that the bigger the change in the magnetic field, the greater increase of energy for the flashlight/generator.
After first shaking our flashlights to make sure our magnetic was ready to move we connected it with a probe and the NXT adapter. A batter was placed in the robot and a cord connected to the computer to record the levels of energy used. We took five different sets of data, each in thirty second intervals but we increased the speed (a.k.a. the number of shakes) each session. Because we had connected it to the computer, we were able to record the data and have it converted onto an excel spreadsheet, shown in the image below.
Though the image above is a little blurry (sadly cellphone cameras don’t do justice when photographing a computer screen), it shows that we began with zero shakes before increasing to fourteen, twenty-one, forty-five, and seventy shakes, respectively. After highlighting the data and entering “SUMQU” onto the spreadsheet it calculated the total voltage we generated in each session. Finally we plotted this information onto a graph. Our results seemed strange at first, because our graph indicated there wasn’t a constant increase of voltage even though we increased the number of shakes each session. Luckily however, the line on the graph demonstrates that there was a rise in electricity generated, so we completed our lab and recorded our data correctly, as shown in the final image below.
This was another interesting class. Using items like the flashlight and magnet helped our group actually understand how things like generators work and how they’re powered. Rather than just reading about it, or hearing about it, we saw hands on (literally) how it worked. All in all, a pretty interesting way to learn about electricity and energy.