I walked to class with Brian, Alex, and one of my lab partners from last week. The morning lecture was an introduction to how to use a digital oscilloscope to measure . After a few demonstrations and clarifying questions, we went into an early lab where we used the oscilloscope to measure the speed of electricity running through wires. It was very cool. We also played around with reflecting electric signals back using an open-ended wire and creating a pulse almost identical to the original versus shorting the end of the wire sending back a reversed pulse or dampening the current, resulting in no pulse at all. The lab really gave each of us an opportunity to experiment with the dials and buttons of the oscilloscope and really get the hang of how to use it.
After the morning lab, Bill gave a lecture on exponential functions. His presentation, as usual, gave me an even deeper understanding of the concept even though I was already familiar with it (in this case, I had been learning about them for many years). Bill used the example of four bugs in a square each trying to catch up to the bug before it so that as one bug moves, its position affects all the bugs behind it, which in turn affects the bug in front of it, thereby affecting its self and so it's position is in fact a factor that determines its position. I am doing a good job of complicating it all, but believe me, when he described it it was very easy to understand. He also showed us a toy car that he had build with an adjustable speed dial on it that trailed behind it so that it moved as the car moved. In this case, the speed of the car was a factor that determined the speed of the car.
At the end of his lecture, he described to us a lab that we would all be doing sometime in the near future where we collect data that describes a non-linear relationship. The unique part about this experiment is that not only do we get to choose our groups, but we also get to decide exactly what non-linear relationship we are going to investigate and set up the design for the lab all on our own. Clearly, the class is going in a more independent and investigative direction which is very exciting.
Today exceptional in that Bill's lecture didn't end 15 minutes late. In fact, today we went to lunch 10 minutes early. It was a Physics Summer Discovery first.
After lunch, we worked more with the oscilloscopes, this time with diodes and resistors in circuit boards instead of just wires. Once we got the hang of that, we moved on to LED lights (light emitting diodes). Using both the oscilloscopes and Logger Pro, we were able to find the wavelength, frequency, and energy that each different color gave off. With that we could find Planck's constant. It was pretty amazing how precisely we could measure these things with this equipment. The results we got were within about 15% of the accepted values.
After class, Mario signed us out and took us to see Swarthmore College. We hopped on a trolley, and then on a train and before we knew it we were standing in the picturesque lawns of Swarthmore. We got maps and took a self-guided walking tour of the campus. The scenery is really incredible and based on the bulletin boards in the main buildings, there are some really interesting groups and clubs active. But Swarthmore is an incredibly tiny campus, and the town, when compared with Berkeley or Philly leaves much to be desired. I do not see myself attending the College in the near future, but it was definitely fun to look around. They even have a climbing tree (the plaque on it said "please climb and laugh") it was quite nice.
For dinner, we went to an Irish pub. I ordered a delicious salmon BLT with thick-cut sweet potato fries. It was a great break from the dorm food.
When we returned to the quad, it was already 8:30. We checked in, had our weekly floor meeting with our RC to restate the rules and make sure everyone was on the same page (apparently the 5th floor lounge is now off limits after another program had a dance there and failed to clean up properly), played a few creative card games and then it was off to bed and the end of another day.