estimation

Dot Physics

Category archives for estimation

What if everyone jumped?

Might as well jump. Jump. Go ahead, jump. – Van Halen Suppose everyone in the world got together and jumped. Would the Earth move? Yes. Would it be noticeable? Time for a calculation. Note: I am almost certain that I have done this before, but I can’t find where. Starting assumptions. 7 billion people. Average…

How tall is that UFO?

You know I wander around the intertubes, right? Who doesn’t? Anyway, I saw this collection of strange google Earth images. Yeah, it is kind of dumb, but this one made me think: That article said the image was from TechEBlog, so there is that. I have no idea what this thing is, but it is…

Size of 91,000 documents

Here is a quick one. One of the big news stories recently was this regarding WikiLeaks and the release of the Afghan War Diary. There could be tons of things to discuss regarding this – but I am not going to do that. The first thing that struck my mind was “over 91,000 documents”. That…

You thought I was going to talk about a problem that math teachers could use, didn’t you? Well, maybe math teachers can use this. (note: when I say “teachers” I really mean “learning facilitators”) It all started when I read this valedictorian speech from Erica Goldson. Here is part of it: “I am now accomplishing…

How fast is the Beacon of Gondor?

The Lord of the Rings trilogy came on TV again recently. My wife and I can’t help but to watch this even though we have it on DVD. Anyway, I was thinking about the part where Gondor sends a signal to Rohan asking them for military aid. Since this was before the invention of email,…

Here is part of a picture some of my friends posted from a recent high school reunion. It may be hard to tell, but this is part of a picture of 7 females all wearing black. I just wanted to show you that they were indeed wearing black without giving away anymore details. If you…

What is Arnold made of?

Of course I am talking about Arnold Schwarzenegger. After looking at how many bullets he carries in Commando, I remembered this scene (also from Commando) (warning: maybe some not great language and some killing. You have been warned) If you don’t want to watch that clip, here is a shot (sorry for the quality). Clearly…

Energy in a hidden battery

Back to the discussion about hiding an electric motor in a pro racing cycle. Before, I looked at a video of Fabian Cancellara to see how his speed and acceleration compare to other bikers. The claim on the internet is that he pulls away so fast that he must have a motor hidden in his…

Oil Spill Estimation

I was going to just leave the oil spill in the gulf topic alone. Not because it isn’t important, obviously it is. Rather, I wasn’t going to do anything because I didn’t really have anything to add to the topic. After a couple of readers requested it, I think I do have something to add.…

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…