I had to cut my portion of the meeting with them short because I was on my way to meet up with my highly esteemed colleague who aided me during my student-teaching, my mentor Steve. It was the end of his spring break as mine was beginning. I got to help him with another demo. This demo is as equally as crazy as the bed of nails demo from December. The topic was heat transfer, the idea is that you can come in contact with very hot surfaces without burning yourself. What can be super hot to touch without burning yourself? You can put your hand in (not on) an oven that is set to 450 degrees Farenheit (232 degrees Celsius), but that's nothing. The air cools too quickly, if it didn't, you would feel cold in 72 degree weather, you would if you live in Arizona at least. We needed to do something the average joe wouldn't dare agree to. How about walking on burning hot charcoals?
I showed up to the demo site (school park property) and found Steve hanging out in his car with the charcoals warming up next to the pit area. Being that it was his spring break, and nobody was at his school. It was a perfect time to share libations while doing a run through of the demo. It helped a lot to shake off the nerves to actually perform this crazy idea. I was all for doing it after I went over the physics of it: generally, the rate at which heat is given off by the charcoal is too quick and the heat absorption rate on the bottom of my feet is just long enough that not a lot of energy is transferred if you can cut short the contact time with the charcoal. The trick is to not run. If you run, you apply more force into the ground, causing closer deeper contact with your feet. Reduce that, walk. You spread the force throughout the whole surface of the bottom of your foot, YOU DO FEEL A LOT OF HEAT, but you dont burn up and leave bad burn marks. So it went well with the test run. Tried it with both wet feet and dry feet. With wet feet, the charcoals might stick, careful. Dry feet, they just get dirty.
My next professional experience was a visit to Lake Forrest College for another monthly meeting with fellow Physics teachers of local high schools, colleges, and university of the Chicago Area: The Illinois State Physics Project. It's a friendly gathering to share ideas and projects that work well to describe a concept or demonstration for classroom use. I have done a previous blog about presenting in front of these guys, and dog-gone it, I presented something new to them this time around, and I knew about doing it long before I got there this time, so I was ready and confident.
Again, I did the introduction as "The young Jerry", I think this time it caught on. Gerry Lietz realized at that moment that he is old. To be nice we will say he is not old but seasoned, very well seasoned. When it was my moment to take the floor, I went over to the storage room next to their lecture area. I pulled out a bicycle and walked it over to the lab table that everyone in the room looked down on. When I placed it on top of the table everyone could see what had happened to it, but that wasn't the point. A tire tube was exposed outside of the rim and the cover of the tire was not fitted on right on the front tire. The gist of what I told them is how it follows...
"I got this bike last summer at a garage sale in Elmhurst. I had a job downtown over the summer and a place to crash a couple nights a week, and I didn't want to drive all the time, I just wanted a bike that would take me from point A to point B with some nice speed on it. This bike however was brought to my attention for a different reason, so I bought it. I was working on fixing the front wheel today when I remembered how this works and that this would be something neat to show everyone as long as you haven't seen this before. It is constructed like a normal bicycle, it has a seat, pedals, handle bars, and it also has multiple rails for the chain to link to, now why do bicycles have such a thing?"
I waited a moment for someone in the audience to respond with the answer "to change gears" which is the correct response...
"To change the gears! How do we normally do that?"
I let the audience take another guess, "just turn the gear shifters"
"Where are my gear shifters?"
just then, the audience of physicists took a closer look at the handle bars of my bike and realized THERE WERE NO SHIFTERS!
"Like I said before, I got this bike for a different reason, I asked the dealer where they were and he said there was no need for them. This type of bike was made in the late nineties and is said to be an Autobike. The gears shift automatically!"
"How does it do that? The gears shift based upon the centripetal acceleration of the back tire that contains weights evenly distributed around the wheel, and they are each held together by a tight spring. As the wheel spins faster, the weights get further from the center pulling away from the springs that are attached to the deraileur and cause the chain to switch to a different sprocket."
Everyone was intrigued, I was pumped. I delivered my presentation the way I wanted to and was even able to demonstrate the changing of the gears by flipping it over and letting the audience see the spring-held weights move further away from the center as the wheel rotated faster. It wasn't too long of a presentation but did get a lot of people coming to me with comments after the meeting was over. I got a giveaway of a henry inductor with some powerful magnets and got to hang out with some big dogs of the physics teaching community.
If you think that's all I did you are dead-wrong!
A couple days later was the real show in front of the students for the fire-walking demo took place. I was a surprise visitor coming back to meet all my former students, and to help Steve guard the location of the fire pit so no ignorant beings thought about touching the hot charcoal. We had a few students from one of the classes guard everything when we both weren't around. Finally we had it setup. It was nice to evenly distribute the charcoals throughout the pit and to continually prove to the students that the charcoals were indeed hot. When they were in doubt, we ripped a sheet out of a phone book and laid it on everything to see it engulfed in flames in a split second. "Yeah, it's still hot!" Steve let the crowd notice what heat transfers were taking place and wanted to show them the effects of heat transfer on different objects. How long would such objects stay hot? How long would our feet stay hot? Would they stay hot long enough to burn us alive if we walked across? The crowd couldn't wait. A few of them got the chance to walk across in their shoes, but I thought that was nothing, I talked down their game as a way for them to bet me that I couldn't do it. Finally Steve went first, with wet feet. The water itself acts as a insulator so he would be safe for a couple of seconds. The crowd was pleased but not too pleased since he did that. There was a bucket to dunk the feet in afterward, but that made sense, we walked on fire, we didn't want to have continual heat sensations acting on our feet, that's crazy! I knew I had to do it, dry. I walked across like it was no sweat. They couldn't believe I came back for this reason, I thought it was the best reason! After it was time for the students to head back in, Steve and I took care of the fire pit but extinguishing and burying everything over. It was funny to see smoke coming out of the ground after a while. We did everything we could with everything we had. It was time to celebrate by showing the other teachers the bottom of our feet and look at them with disbelief. Our pride did get the best of us. During one of the free periods that morning, he asked how I felt. "Seriously, this feels different from last time, I think i sense a couple blisters on the sides of my feet, sorta irritating!" Steve felt the same, "Yeah I know, this is unbearable, I think I am going to call it a half-day today!" I was blown away by that, until he asked, "Do you think you can teach a couple of my classes?" I am back to student teaching again! I told him I wouldn't mind, but I had to go to the university for a luncheon, and number two, I was still on spring break! "You don't have to teach all of them" he said "just maybe the next two and we will leave the last period to so-and-so." I told him I would take just one because there were an easier group and would have appreciated my return more. The other part to all of this is that at the time, it was illegal for me to teach at that school because I was not registered all the way through with the City. I did it anyways, had a nice lesson on waves. Anyone else would have let them do whatever they wanted, but I had a plan and engaged it. All went well, the students noticed I am a lot more confident in front of them, only because I knew what I was talking about, and I got use to teaching over the last couple of months. The period ended and I only had some time to say hello to a few people coming in the next period, I was done with the school until next time, whenever that may be.
I went to a luncheon with former colleagues I worked by when I was getting certified to teach. There was a Society of Physics Students meeting, and after I introduced myself, the older students were able to point to all the new members that I was a former President of the society. I wasn't much of a president but I did come up with many new projects to do before I took the position. The same year I took it I student taught, so I was hardly ever there. I had a nice talks with professors and soon to be teachers about how everything is going. I gave them as much advice as any new teacher can. Which of course is not much.
The next day, I finally got the bike fixed up. I took it with me to get to another luncheon at Northwestern University and used it to ride a few blocks from where I parked. Some of the people attending the luncheon were able to recognize me from earlier that week, "You are the guy who brought the bike!"
"I brought it to campus." I told them.
The point of the luncheon was more of a get-together with fellow physics teachers in the Chicago area. The man who wanted us to me was a nobel physicist Leon Lederman. He had spent a lot of time in Illinois with both science and science education. My theory is that if you can get anything to work here, you can get it to work anywhere, just like the town of Peoria might be used. His plan is to reverse the order the way the sciences are taught, Physics First is the name of this program, followed by chemistry, and then biology. During the luncheon, he told us he realized that this might sound scary: A froshman taking physics! That sounds scary to not only the student, but sometimes also the teacher! "They should call it Biology on Top!" that sounds a little more reassuring. He has been long since retired and is now trying to transform the entire science curriculum. I dont know yet where I stand on this but I do see a lot of signs dealing with the way physics ought to be taught. I did tell him that I am doing Physics first, but I feel like I am going to have to do Chemistry first. My physical science class is a froshman science introduction course that has the first year more chemistry based, and the second half of the year physics based. I know I am going to teach the same thing twice to the students with a couple of years in between. This needs to get straightened out. The science department is already setting up a new curriculum that will mainstream health science as a way to catch people's attention to come to this school. Luckily as a physics teacher, I may not have to deal too much with this change, but I will have to let certain board members take my students on mini-field trips to the hospital to learn about different health careers, whatever.
So that is my spring break in a nut-shell. I did have a lot of fun, and it was definitely worth it.
More to come as the year is ending.
