Dot Physics

Archives for April, 2009

Let them have computers

Announcement: There is a ton of extra money for education of teachers. You should submit a grant proposal. Hey, let’s submit a proposal and get laptops for a whole bunch of students. To me, this is like giving morphine to people with the flu. It will make them feel better, but doesn’t really fix the…

Super Fast Motorcycle

ZapperZ already beat me to this, but if it is worth doing once it is worth doing again. Here is a video of an electric motorcycle that can apparently go from 0 to 60 mph in 1 second. What acceleration would this have? If you want, you can look at my stuff on kinematics, but…

In the second Cat in the Hat book (I think it is the second one), the Cat reveals that he has more smaller cats under his hat. They are labeled A – Z with Z being so small you can’t even see. Question: What is the sequence of sizes for successive cats? How big would…

It’s odd that I have talked about these forces so much. First, I talked about how centrifugal forces were not real and the difference between centrifugal and centripetal forces. Then I talked about how sometimes, fake forces are good. Finally, I talked about the origin of the words centrifugal and centripetal. (note: “talked about” means…

A student in my office temporarily confused the words centripetal and centrifugal. This started me thinking about these two words. They mean different things, but do sound and look similar. I have previously talked about the difference between fake and non-fake forces, but let me quickly define these two: Centripetal: This is the force needed…

I have already indirectly talked about this before, but I see it more and more. Say you have a show. It has to be more than entertaining, it has to educational. How do you make things educational? Describe the physics behind the concepts – right? Fine. How do you explain stuff? It’s simple. Just make…

Some time ago I was looking for materials to possibly build a foucault pendulum. Of course the first step is google. There was a site that suggested two old issues of Scientific American, and it happens that we have tons of old Scientific Americans in the store room. I found the two that I needed.…

Why are sparks blue?

I am not sure if First Excited State posted this as a blog entry, but it was mentioned on twitter. Question: why are sparks blue? My first gut response was that this is the blackbody color. Wrong for several reasons. The short answer is that sparks are blue because of the colors given off from…

First: Car Talk is awesome. I wish I could come up with some class activities that help students become as good at trouble shooting and critical thinking as Tom and Ray are. Anyway, they are quite entertaining. So, my Dad called and told me he heard a discussion on Car Talk about the effect DC…

Some things about science

I have been meaning to write about this for quite some time. Really, I wanted to reply to Chad’s article on science at Uncertain Principles, but you know how things go. So, here are my key and interesting points about science in random order.