Monday, March 16, 2009

Four more vehicle-related talks...

Over the last three weeks, I have given two talks each to the geometry classes and to the algebra class. In the geometry classes I first brought in a discussion about the research I did on explosives two years ago as an undergraduate. I began with a short video clip of a land mine exploding on a road in Iraq, which really caught their attention better than I've been able to all year. All three of the classes were fully engaged and listening throughout the presentation. I began by discussing Humvee safety and how the vehicles and occupants would be affected by land mines, and then asked the students how we could learn about the effects of land mines on Humvees. This eventually led us to the idea of scaled-down tests, which fits in nicely with their recent unit on proportions and ratios. From there, I discussed the scaled-down explosive testing I did in Maryland and we calculated how it was scaled down proportionally. The students were very attentive and I was very pleased with how it went.

The second talk I gave was today, and I first went through the MITE recruitment presentation to discuss the summer program and encourage them to think about it and apply. I skipped a lot of the details on the different fields of engineering because I didn't want to lose them, but in 3rd hour they asked several questions about the engineering types, so some of them were clearly interested. I passed out handouts with the website for those who were still interested. After I finished this, I went into a powerpoint that I prepared about how cars turn (handling). Following last week's success, I began with a video of a car spinning out, which caught their attention fairly well. We then discussed why a vehicle might spin out (and they all were able to come up with a lot of good answers before I said anything), and discussed the geometry of a turning car. We talked about the angles that the wheels are turning, and then the angles that the tires might be slipping against the road. I think today's talks went very well.

The algebra classes have been a different story. Two weeks ago I gave a talk on hybrid and electric vehicles, based on the interest they showed in the first week, and last week I brought in a discussion on the Michigan Solar Car team project. For both of these talks, I wanted to go through some of the math and science behind the vehicles. The first one went okay, and we calculated the difference in emissions between an all-electric Tesla Roadster and a Toyota Corolla and found that the Tesla has slightly lower emissions. I then showed them how to calculate what type of efficiency we'd need in a conventional car to equal the emissions of the Roadster, and it turned out to be around 42 mpg. We mentioned that a Prius gets higher mileage than this, so a Prius would actually be better on the environment that a Roadster (specifically with the power generation distribution in Michigan). I thought this was very interesting, and some of the students followed, but it was frustrating trying to get through the talk because there are still a lot of distractions and interruptions and overall rudeness. In the talk on the solar car, we did a calculation of how much solar panel area a normal car (Ford Taurus) would need to get the same power it has, and it turned out to be over 100 times the area it has. This actually explained a question that someone had in one of the previous lectures, when someone asked why we don't have solar-powered cars. Very few of the students seemed to listen to this talk, but in both talks they had a lot of questions at the end (some of which I had already answered during the presentation had they been listening). This frustrates me, but it also challenges me to think of ways to prepare better talks for my particular audience.

Today I did not prepare a talk for fifth hour, but they had an in-class problem set to work on, and I walked around to provide help where possible. There was an incident that sticks out in my mind where I heard a student say "I don't understand this", so I went over and asked her which problem she was having trouble with. She replied "I don't need help," and I said that I heard her say that she didn't understand something, and I am here to help with that type of problem. There may have been another exchange with her refusing help, and then she replied with "I don't want YOUR help. You don't even know me." I responded to her, saying "I don't understand why you are so rude to me," and calmly walked away. This really bothers me, because I really can't see why a student would be so rude to me, when I have shown her as much respect as possible. I guess I'll have to try again next time.