So, you knew I was going to make some mistakes on the physics of scooting - right? I don't think these mistakes are major and they don't take away from the main idea. Read More...

Tags: forces, kinematics, modeling, momentum

There you are, in your rolling chair. You need that extra pencil, it is just a few feet away but out of reach. For some reason, you don't want to touch your feet to the floor. How do you get that pencil? You scoot. Still don't get it? Here is an example:

Why do people scoot? I don't know. My kids do it too. When does a human learn to scoot? How does a scoot work? Really, I am just going to answer that last question, but the others are interesting also. Read More...

Tags: forces, kinematics, modeling, momentum

I like numerical calculations. I think they are useful. But what should I use to create my calculations in? I am still not sure. Here are my options:

• VPython: I think this is the easiest for me to create things in. Python is uber-simple and the visual module has most of what I want. VPython 4 is currently in development and will run in Mac OS X without using X11 - so that is good. One bad thing about vpython is that it seems a little slower than java. I could be wrong about that though. The other big problem with vpython is the question of how to share simulations. It would be great if you could embed vpython in a webpage, but you can't. A user would have to download the code, install vpython and run it. This is ok if one is using it for courses, but not if you want a more general audience to look at it. Oh, vpython is free. One more thing, I feel comfortable creating stuff in vpython.
• Java. On its own, I probably wouldn't consider this. However, there is opensource physics. Opensource physics is a set of java "stuff" that allows you to create java calculations without doing all the crazy (programming) stuff. You still have to compile the programs, but it gets a lot of the difficult stuff out of the way. This stuff looks pretty powerful, but with great power comes a greater responsibility to do good, and I am just not sure I can do good. Really the problem is that java is pretty darn complicated compared to vpython. I can crank out some pretty simple stuff in vpython WAY quicker than in java. On the plus side, java is free AND you can make apps that can be run from the web, so a user would only need to have java installed - many do have this.
• Flash: Flash is pretty with its vector-based graphics. Also, I am told it can do many of the things java can do. But to tell you the truth, I really don't "get it". What Josh, what don't you get? So, its a robot that turns into a building? What's fun about that? I tried making a simple program, but there are too many new terms that just plain confuse me. Another problem is that this sucker is not free, nor cheap. I have a friend that is big into flash, he keeps telling me I can get into it fairly quickly. So the two big pluses are - it looks good, runs in web pages. But it is not free. If I get into flash and I want students to do flash stuff, they can't because they won't have it. Also, what is AIR? Is that free? I never figured out what air is.
• M.S. Excel. What? Are you kidding? This is a great tool for basic calculations and a great way to involve students, but I can't stand using spreadsheets for calculations. I hate highlighting cells and graphing and all that stuff. Yes, there are some great free spreadsheets, but for me I will not use them for this stuff.

So that is where I am. Stuck.

Tags: modeling, numerical , computer

Ford, why are you the way you are? Do you actually have people look at your commercials? Or do you just assume that you can say and show whatever you want and I will buy a truck? I am sorry, I shouldn't say that. I do enjoy analyzing your commercials - so, please continue.
Ford's latest F150 commercial shows a big thing dropping from a helicopter to the bed of an F150. The claim is that Ford is awesome. 30,000 lbs awesome. Let's check this out.
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Tags: video, modeling, momentum, forces, kinematics