Dot Physics

Archives for July, 2009

The Anacapa Society is a professional organization promoting research in all areas of theoretical and computational physics at primarily undergraduate institutions. If you are at such an institution, I would recommend taking a look and perhaps joining. In my views, undergraduate research is one of the best things about an undergraduate institution. What better way…

Chad is posting some very useful stuff at Uncertain Principles. Basically, he has quite a few scientists that are not professors or such answering some questions. This is a great way for students to get a feel for what scientists actually do. If you don’t subscribe to Chad’s blog, you totally should. A great resource…

Accelerometer Version-2

So, I built a new accelerometer. Why? The jelly-jar one was just not doing it for me. Plus, the cork was starting to make the water all yellowy. It was a good start, but I can do better. What was wrong with the jelly-jar one? First, it didn’t let the cork move very far before…

ROYGBIV and Newton

This comes up everytime I teach physics for elementary education majors. The curriculum I use (Physics for Everyday Thinking – which is awesome) says that the colors in white light are ROYGBV (Red-Orange-Yellow-Green-Blue-Violet). Typically, I will get a student that says “Hey! What about indigo? Shouldn’t it be ROYGBIV?” My first reaction to this was…

Basics: Centripetal Acceleration

pre-reqs: vectors, kinematics I haven’t done a “basics” topic in quite some time. It’s odd, I have used centripetal acceleration quite often, but I never derived the expression that I use. To get to the point, the magnitude of the acceleration of an object moving in a circle is: Also, the direction of this acceleration…

Note to self: don’t do the mechanical equivalent of heat lab again. It doesn’t really work that well and there are better labs to do. So, what is the mechanical equivalent of heat lab? It is actually a pretty cool idea. Take and object and drop it. What happens to the kinetic energy the object…

Yesterday, I uploaded a post from my old site about slowing down time to make videos look like they were on the moon. If you haven’t read that, the short story is that it doesn’t look right when speed Apollo videos up so that the acceleration is -9.8 m/s2. What started that whole thing was…

Note: This is a repost from my old site. Time to move it over. First, what is different about motion on the moon and on Earth? Since the moon has a smaller mass in spite of its smaller size*, the moon has a smaller gravitational field. The gravitational field on the surface of the moon…

This has been on my list for quite some time. Really, it must be since i posted about measuring acceleration in free fall with an iphone. So, this post will be all about accelerometers. How does an accelerometer work? Really, an accelerometer measures force some way on a known mass. Let me show an extremely…

My friend J sent me a link to this gyrobike (http://www.thegyrobike.com/index.php). From what I can tell, it’s a flywheel that you put in the front wheel of a bike. The site claims that this will help kids learn how to ride a bike. So, what do I think? Clearly, this is a real product, but…