Engineering - Math & Science in Society Class Summary 2/17/14

with Ed Insel

Conducting Research

We started class with a review of the students’ Google Search results. The main findings were: 

1. There’s a wide variation in the number of results we each found.
   
2. Running several searches several times produced different results.
   
3. More and more results are found if you run the search repeatedly.
   
4. The most reputable sources are sometimes not listed until the third page or later.
   
5. Google isn’t the only or the best search engine - there’s Yahoo, Bing, and Dogpile, too. 
   

I gave them a list of domains on the first five pages of the climate change search and highlighted the ones I’ve found to be reliable and would read first.

We then decided “climate change” was a better description than “global warming”. To give the class a more general decision-making framework, I explained two types of error states to guide their thinking. The first, called “gamma” error, is when there is no problem but you’ve decided to take action just in case. The second, called “delta” error, is when there is in fact a problem but you take no action. Gamma error means committing resources (money, materials, personnel, etc.) to something that may or may not be a problem. Delta error takes no resources but eventually leads to serious problems. This framework makes it easier to decide on a proper course of action even when scientists cannot agree on the true nature of a situation – it’s what engineers do!

Connecting to Current Events

For current events I shared the success that Lawrence Livermore National Laboratories recently reported. Newspapers reported it, but the best information comes from the LLNL site – why rely on someone else to interpret information you can read yourself? Using lasers, they’ve ignited a nuclear fusion reaction that gives off more energy than it consumes. We also discussed the broad media coverage of the drought in California but there has been very limited mention of the discovery of a vast amount of fresh water in aquifers under the ocean floor that are easily reachable drilling from onshore.

For the last 30 minutes of class the students worked on a project to experimentally determine the numerical value of pi (π). They measured the diameter (d) and circumference (C) of seven objects and will use the equation C = πd to calculate pi.

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Homework for Next Session

As soon as possible, one member of each team should email me their data (object, diameter, and circumference). Each student should calculate π for each object and then average them to come up with a single value for π. They are using their Engineering Journals to keep records of all their work. In next week’s warm-up we’ll compare the teams’ calculations and see whose value comes closest to the theoretical value. This will lead us into ways to quantify data variation and identify the sources of error.