Dot Physics

Archives for November, 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,…

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…

Orbital Speed and Buzz Out Loud

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 once when I posted my [Optimal…

Cool things the Greeks did in astronomy

One of things I like to think about in science is “how do we know that?” It is interesting how one thing builds on another. This is a story of how the Greeks estimated the distance from the Earth to the Sun (an important idea in the development of the model of the solar system).…

Georgia Tech Football Sign – Physics?

Georgia Tech is playing Miami (not the real Miami, the other one Miami Florida). Right after a commercial, the camera shows this sign from a student (or just person) at the game: ![Gtphys](http://scienceblogs.com/dotphysics/wp-content/uploads/2008/11/gtphys.jpg) (Sorry if the image isn’t that great.) I had to pause the game and take a closer look at this sign. I…

Colbert gets an A in physics.

Rarely am I up late enough to watch the Colbert Report, but by chance I saw it last night. I know Stephen Colbert is a big fan of Dot Physics, and so this is a message to him. Stevie, good job. Here is what he said during his show on the “The Word” segment. Just…

Ford F-150 vs. a Plane. Really?

Big trucks are not as popular as they used to be, but gas prices are going down so maybe this commercial for the ford F-150 will start showing up again: They say its a real demonstration, but it has seemed odd to me. (they also say this is a professional driver on a closed course…

This must have been mentioned in a previous post, but I am too lazy to search. Anyway, I think have enough stuff here (at blog.dotphys.net) to finish moving stuff from my previous version of the blog. What does this mean and why do you care? You care because if you are one of the two…

Atwood’s machine is the name of a device that looks like this: Also known as “two masses on a pulley”. Surprisingly, this simple device comes up a lot in intro physics texts. It also brings up some interesting issues. I will go over the basic way to solve a problem like this (as an example)…

Here is a video of a guy jumping 35 feet into a pool of water only 1 foot deep. UPDATE: Apparently, that video went away. Here is another version. How does this work?