Dot Physics

Archives for September, 2008

Today I was talking about electric potential. My favorite analogy for electric potential energy is gravitational potential energy. But electric potential is something different. Electric potential (commonly called potential) can be defined as: So, V is the electric potential in units of Joules per Coulomb or Volts. What about gravitational potential? I am sure some…

LaTeX equation test

I use equations quite a bit. What I have been doing is writing the equations in LaTeX and then taking a screen capture of the output. I think this makes nice looking equations, but it sure takes a while. Here I am testing [LaTeX for WordPress plugin](http://wordpress.org/extend/plugins/latex/). The following *should* be some equations: $$\vec{F}_\text{net}=\frac{d\vec{p}}{dt}$$ $$a^2+b^2=c^2$$…

**pre reqs:** [kinematics](http://scienceblogs.com/dotphysics/2008/09/basics-kinematics.php) Suppose there is some experiment in which you throw a ball up and collect position and time data (with video analysis). What do you do with this data? Your instructor told you to make a graph, but how do you do that? Here is the fictional data you (or I) collected: ![data2](http://scienceblogs.com/dotphysics/wp-content/uploads/2008/09/data2.jpg)…

Mr. Miyagi and learning

So here I was in thermal physics class. The students were talking about the assigned homework and then asked: “can’t we get some homework credit for this? Why are we even doing this?” Immediately in my head popped “wax on, wax off”. This was the same situation Mr. Miyagi (from [The Karate Kid](http://en.wikipedia.org/wiki/The_Karate_Kid)) was in…

Basics: Fundamentals of Algebra

**pre-reqs:** *none* I know who you are. I have seen you before and talked to you before. You are taking introductory physics and you are scared. Why does this have to be so difficult? It seems like there are a bazillion equations. Calm down, I will try to help. First, realize that algebra and trig…

I like computers, really I do. Computational physics is a good thing. However, there is a small problem. The problem is that there seems to be a large number of people out there that treat numerical methods and simulations as something different than theoretical calculations. You can tell who these people are because they refer…

There was this commercial on the radio about Trane heating and cooling units. The ad claimed that the units could use up to 50% less energy than your existing unit. This started me thinking (because before that I was in a complete state of non-thinking). Do you remember the Y2K problem? Basically, when people started…

Basics: Vectors and Vector Addition

**pre-reqs:** trig Think of the following two things. Temperature and wind speed. These are two different things that you could measure, but there is one big difference. Wind speed has two parts to it – how fast and which direction. Temperature is just one thing (no direction). Temperature is an example of a scalar quantity…

Amazing Blob Jump Launch Video Analysis

Can you believe it? Have you seen this video? Are you thinking what I am thinking? WOW. How could these people not follow my rules for cool internet video. Once again, here they are: 1 Keep the camera stationary. This way I don’t have to keep moving the origin in the movie. 2 Don’t Zoom.…

A note about some old posts returning

I am sure I mentioned that I am moving to WordPress (from Rapidweaver). I would like to have all my important posts moved. To do this, I am just going to repost them in WordPress. Maybe there is a better way, but I am not sure. So, the point is that if you have been…