Rhett Allain
rallain
Posts by this author
January 8, 2009
Here is an article from Wired.com that talks about a used cooking oil generator. It's a really neat idea in that the oil is right there anyway. Here is my problem - from the article:
A new garage-engineered generator burns the waste oil from restaurants' deep fryers to generate electricity and…
January 8, 2009
I am going to tell a story and then calculate the probability of part of it happening. Really, it's just an excuse for me to put this online (since no one got hurt).
My parents have this house on a lake, but it is really hilly. There is a dock down there, but it is like a bajillion stairs to get…
January 7, 2009
I saw this video posted on Physics and Physicists:
It reminded me that I had at one point tried to analyze this. I had actually posted something about this on the first generation of my blog (which no longer exists). I have found the analysis, and here it is from the archives. Thanks ZZ for…
January 6, 2009
The Teaching Professor has a short note about students cramming for exams. The article talks about how you should deal with students cramming for exams. It includes the correct answer: you shouldn't do anything accept maybe change your tests.
What is the purpose of a test? It is some way to…
January 5, 2009
I finally saw the movie WALL-E. Good flick, I liked it. There was, however, one part I must comment on. You know I can't help myself. I feel like the shark Bruce in Finding Nemo. I try not to attack, but there is a tiny drop of blood in the water. Here is the scene that I want to talk about:…
January 3, 2009
I finally saw the movie Iron Man. It was good. I feel that I am qualified to evaluate the movie. When I was in high school, I was totally into comic books. Mostly Spider-man, but I still have a significant collection of Iron Man comics. Ok, now you know I am not an Iron Man attacker. I will…
December 30, 2008
Just to be clear, Newton probably didn't have a portable video camera. I do. I have one of these Flip Mino pocket cameras. Very nice. You can put it in your pocket. However, there is a problem with cameras like these (think of video from camera phones). The problem is the mass, it is too…
December 29, 2008
In part I of this post, I talked about the basics of projectile motion with no air resistance. Also in that post, I showed that (without air resistance) the angle to throw a ball for maximum range is 45 degrees. When throwing a football, there is some air resistance this means that 45 degree is…
December 26, 2008
College football season is coming to an end (I guess technically, the season is over - it is bowl season). Anyway, this is something I wanted to do a long time ago, but I kept getting side tracked. If I don't do it now, I will never do it. Most people know that a ball without air resistance (…
December 23, 2008
Clearly, I am not a professional blogger. I am an amateur. This is because I was under the impression that only amateur bloggers could compete in the blogging olympics. When did they change these rules? Anyway, Adam Weiner did a physics-based analysis of the latest Star Trek movie trailer. Here…
December 22, 2008
First, don't play with fire. Fire is dangerous. You can get hurt. Here is a video of two guys trying to (presumably) make the Miami Heat flaming basketball.
Note: the above is just a picture link to the actual movie. Embedding the movie was doing some weird stuff. In the movie, two guys pour…
December 19, 2008
I am sure I have mentioned the Discovery show Time Warp before. The basic idea of the show is to find how many cool things they can look at with an ultra slow motion video camera (btw - this is on my christmas list).
So, I have seen this Samurai guy on the show twice. Yes, he has a big sword.…
December 19, 2008
I have been searching for where I found this link, if it was your blog please forgive me for not linking. Here is a link to Common misconceptions in science from wikipedia. Looks fun. Really, I am just posting this so I won't forget to come back to it sometime.
December 18, 2008
I saw this video on several places. It shows an astronaut playing with a CD player.
I wish I were an astronaut. I would probably not stop throwing up though. It would still be worth it. You can only throw up so much right? (I know the answer to this question). Anyway, this is a really cool…
December 16, 2008
Wow. I wrote a post about Directly Down Wind Faster Than The Wind (DWFTTW) vehicles. At the time of this post, there are 37 comments for the original post. That is way more than I expected. This is very popular topic. Clearly, it brings a lot attention to Dot Physics. The first question - is…
December 15, 2008
Maybe you have seen some of my posts on basic topics. One of the original ideas I had for creating the "basics" posts was so that I would not need to keep repeatedly explaining what the fundamental physics concepts were for each post. I can only explain the work-energy principle so many times…
December 14, 2008
I saw this over at ScienceGeekGirl which links to a video from two high school chemistry teachers in Colorado. The two teachers describe how they modified their chemistry courses. ScienceGeekGirl gives an excellent summary of their changes and motivations, so here is the short and dirty version:…
December 12, 2008
Pre Reqs: momentum principle, forces,energy, vectors
Really, there is not much new here. This is an introduction to objects that interact. To describe this, I will need to pull several different ideas together (that you have probably already looked at). Let me start with a simple case. Suppose…
December 11, 2008
I was going to go to school and give a final. I guess that is not going to happen now. My daughter measured 7 inches of snow - in Hammond, Louisiana (50 miles from New Orleans). Here are some pictures - more to come (plus video).
From Winter Storm 2008
From Winter Storm 2008…
December 10, 2008
There is something that has been bothering me about students learning in college. The question is, how much do I treat students like adults and how much do I treat them like children? I have been leaning towards treating them like adults. For example: do I require them to come to class? Right…
December 10, 2008
A commenter (Joe) suggested I look at vehicles powered by the wind that can move faster than the wind. This also came up on Swans on Tea. One of Joe's points was that I should do this BEFORE MythBuster's gets to it. And so I shall. I know this is one of those topics that can never really be won…
December 9, 2008
VPython 5.0 is mostly out (in release candidate). To tell you the truth, I have been holding off on some vpython programs because I wanted to do them in the NEW vpython, not the OLD vpython. So, if you want to get the new vpython, go to http://vpython.org/index5.html. What is so great about…
December 6, 2008
This comes from Buzz Out Loud Episode 865 which got the story from Slashdot regarding a possible new technology that would use piezoelectric devices to charge cell phones while you talk. The original article the slashdot story pointed to talked mostly about the advances in piezoelectric devices,…
December 5, 2008
Let me start off by saying I think I first read about this on HowStuffWorks.com (many years ago). So, why are christmas lights so cool? They are cool because they are a whole bunch of lights in series, but they still work if one of the bulbs gets burnt out. If you are not familiar with circuits…
December 4, 2008
Ok - I like Alabama football (sorry, but it's true). There is a clip on youtube of the end of the Alabama-Auburn game where the fans sing the traditional "Rammer Jammer". If you don't know what that is, don't worry. I am not sure I completely approve of the cheer, but it is a tradition. If you…
December 2, 2008
For many people, it is the time of the year to put the bikes away. I live in Louisiana, so now is the time to get the bikes out (too hot in the summer). Learning to ride a bike is a curious thing. Most parents use training wheels to get kids started. I do not think this is the best strategy.…
December 1, 2008
This is something I have thought about for some time. It is also something I (as a father of 4) have a lot of experience with. The problem is these infant car carriers. In the car they are not a problem. The problem is out of the car. Not sure what I am talking about? Here is a picture:
I…
November 25, 2008
You see this all the time in textbooks:
This is often described as "the acceleration due to gravity". Is this really the best thing to call this? No. A better name would be "the local gravitational field" and list it in units of:
Where does g come from? The usual source is from the weight, or…
November 24, 2008
This is an old video, but still interesting. In this video clip, Kobe Bryant jumps over a pool of snakes.
You are probably thinking what I thought when I see that - this doesn't look real. Really, it must be fake. Why would Kobe jump over a pool of snakes? Isn't that dangerous (even if there…
November 23, 2008
One of my favorite podcasts to listen to while driving or mowing the lawn is [Buzz Out Loud](http://bol.cnet.com). Buzz Out Loud (BOL) is basically just a tech-based podcast, but very entertaining. Anyway, as part of my attention seeking disorder, I try to get mentioned on the show. I succeeded…