Class today was very laid back. We started off the day with our speed of light lab. Since we had already set up our circuits, all that was left to do was line up our laser with a mirror across a dark hall in such a way that it bounced back and hit our second photo receptor just right (the first sensor was placed next to a beam splitter in front of the laser. Both receptors were attached to an oscilloscope so we could determine the delay between the two waves (it came out to about 8 nanoseconds). Because we knew the length that the light had to travel from the first sensor, to the mirror and back to the second sensor, we were able to measure the speed at about 3.4 x 10^8 m/s, which is not too far off the accepted value. We were given two hours to collect our data and make our calculations, but because my group finished early, we had about 30 minutes to kick back before our guest lecture.
It was good we were given that time because after a short break, I was able to give all of my attention to Ken Lande when it was time for his lecture to begin. Dr. Lande spoke to us about the energy crisis, how long our current consumption of petroleum can be sustained, and the effects waste products such as CO2 emissions are having on the environment.
Once he convinced us that an alternate source of energy was necessary, he discussed possible solutions. I was surprised at how inefficient the current sources of green energy are. For instance, in order to power the united states with exclusively solar energy, an area twice the size pf Pennsylvania would need to be covered with solar panels. Even more shocking was the amount of land that would be needed to grow crops for bio fuels to power the country: 1/6 of the area of the United States, which would not leave very much room for agriculture. We also discussed fission reactors, but after the disaster in Japan, people are hesitant to rely on something so potentially hazardous. Additionally, in order to rely on fission reactors for energy, we would need to increase the number of plants we currently have by a factor of five. Dr. Lande maintained that the most promising alternate energy source is wind turbines. Only half a million wind turbines would provide enough energy to free us from our dependence on fossil fuels, which would only cost about $200 million a year (only a fraction of what we spend on automobile gasoline).
I appreciated his lecture for its practicality in the real world, in fact he often teaches classes at Wharton school of Business because there is so much money going into alternate energy sources. No wonder too, it is arguably the most pressing issue the world faces today. Me and Brian discussed its importance and the lecture in depth as we walked to lunch.
When we returned, we were given time to do whatever it was we needed to get done. For me that was working with my Hershey Park group on making a PowerPoint for our presentation tomorrow. We wrote up an analysis, slapped a couple graphs of the data we collected, added a video and called it a day.
After class, I went with a book and read for a while by the coy pond. It was very relaxing and it allowed me to sit back and let time move a little slower for a while. With only three days left, I want to get everything I can out of the time I have.