Bill filled the first two and a half hours of the morning with different demos. As the man in charge of UPenn’s demonstration lab, Bill knows exactly which demos are the most illustrative, relevant, and fun. Some of my favorites involved suspending soap bubbles in midair to show that carbon dioxide has a higher density than air, shooting ball bearings out of a blowgun to prove that gravity doesn’t discriminate between ball bearings or Barney dinosaurs, and creating make-shift hot air balloons with a toaster and some garbage bags to demonstrate that hot air rises. The most memorable demonstration was when Bill turned himself into the demonstration by hanging from the ceiling with some carabineers and a garage door sized spring.
|When your teacher shows up to class in a T-shirt that says "I am a professional. Do not try this at home." you know that class is going to be exciting|
Following the demonstrations, we were joined by Dr. Justin Khoury, a particle cosmologist at UPenn. We’ve had four physicists speak with us about the history of the universe in the past week, but Dr. Khoury put a new spin on things in that he discussed multiple theories about the beginning of the universe. He talked about two ideas, inflation and the ekpyrotic universe. Apparently, some of Mark Devlin’s research involves searching for gravitational waves in the beginnings of the universe that would help determine which model is more probable.
In the afternoon, we started on the two-day project that Bill compared to a term paper. Our assignment is to measure the speed of light using PN diodes, red lasers, and oscilloscopes. It combines aspects from optics and electricity and tests our knowledge of different physics machines, so it definitely feels like a final. Thankfully, Bill, Ryan, and Craig are around in case we need any assistance, so it’s pretty low-stress.