Dot Physics

Archives for March, 2010

Density of Wood

This isn’t much – really it is part of another post I am working on. The point of this post is to calculate the density of this piece of wood. Really, there is a reason for this. I saw this little stick (sticklette?) and noticed that it was very cylindrically shaped. So, what if I…

Apolo Ohno’s Slime Jump

Here is a quick Apolo Ohno quiz. Which one of these pictures is fake? If you picked picture B – you are probably correct. That is a picture of “Apolo” being catapulted into a pool of slime at the Nickelodeon awards show (click on the link to see the video – I don’t think I…

Diver in a bottle

I am surprised at how many people (chemistry faculty included) have never seen this demo. (oh, technically it is called a cartesian diver demo) Basically, you put some floating object that has an air space in a closed bottle of water. When you squeeze it, the diver goes down. For my setup, I used a…

Re-thinking physical science

I am teaching physical science this semester. It appears that I will be teaching it again this summer. Ideally, I would like to switch to something like Physics and Everyday Thinking for large lecture courses. A course like this is being developed, but it isn’t quite finished. Also, the current version includes chemistry and physics.…

Could cars slow down the Earth?

Time for another Fermi problem. There was a recent story in Science News that talked about the effects of the Chilean quakes on the Earth’s rotation. The basic idea is that some ginmourmous amounts of rock moved closer to the Earth’s center. Since the angular momentum of the Earth is conserved, the angular rotation rate…

Think Thank Thunk is a relatively new blog from Shawn Cornally, a high school math and science teacher. I have found his posts to be quite entertaining. In Shawn’s latest post, he talks about grades. You know I like to talk about grades. Shawn puts teacher into two groups in regards to their ideas about…

Pressure demo: suction

How does a suction cup work? It is all about the atmosphere. Here is a demo. Take some type of “suction cup” device. In this case, I used a toy dart. Stick it to something smooth and lift it up. Like this: What lifts up the metal block? The atmosphere. Diagram time: But this isn’t…

I already looked at ESPN’s Sport Science episode where they calculate that Marshawn Lynch produces 54,000 watts when pulling some tires. Yes, that is way too high. However, what would happen if some was actually that powerful? What could that person do? How fast could they run 100 meters? That is what I am going…

Debris field for a broken meteor

I happened to catch two parts of two different episodes of Meteorite Men – a show about two guys that look for meteorites. In both of the snippets I saw, they were talking about a debris field for a meteor that breaks up. In these fields, the larger chunks of the meteorite are further down…

Why do your ears hurt underwater?

This is a topic that I am going to talk about in my physical science class. Might as well make a post about it, right? Here is the deal. You are in a pool. You drop a quarter in the deep end and swim down to get it. I know the first thing you are…