Built on Facts

I’m out of town for the weekend, and though I am not around to update this site it’s smart enough to update itself. Well, anyway it’s smart enough to schedule this post for Saturday morning when I’m actually typing this on Thursday night. I won’t exactly be in an internet-free wilderness, but I’ll [...]

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See that equation there? It’s the unsung hero of Maxwell’s equations. It says in English, “This is where I would tell you how magnetic fields are generated from magnetic charges, but there aren’t any such thing as magnetic charges.”
In its integral form as above, it’s usually the second of Maxwell’s equations that my [...]

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I gave this quiz to my Physics 208 class this Monday, modified slightly from one of the textbook homework problems. I was going to work it out here, but I think I’ll leave the solution as a challenge for you.
A straight conducting wire of mass M and length L is placed on a frictionless [...]

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Inside Higher Ed has an article about graduate students at the University of South Carolina.  Seems they don’t make very much money for their work.  By not very much, I mean it’s about the same as the average income… in Brazil.
Graduate students at South Carolina make an average annual stipend of $9,590, a sum that [...]

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Lots of times we might have a complicated function which we wish were less complicated. Take the differential equation describing the simple pendulum, for instance:

I can’t solve that one explicitly. Nobody can - the sin term prevents a closed-form solution and so nearly the only practical way to work with it is to [...]

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The Large Hadron Collider is scheduled to come online in a matter of months.  For all the thousands of theorists working in high-energy physics, SUSY, string theory, and related topics, no one really knows what kinds of new particles are going to be coming out of the collision point.  This, of course, is the entire [...]

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How tall are you? You might give an answer in feet and inches if you’re an American, or in meters most other places. And if you give than answer, I’ll have a good understanding of how tall you are - all because we’re using the same units of measurement. In practice your [...]

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A few days ago I wrote about how to move in space, you needed to bring along something to push against. Dr. Pion objected. “It’s not what you push against that makes you move, it’s what pushes against you.”, if I can paraphrase.
I thought that was a silly objection. It’s true, but [...]

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Apollo 11 launch
July, 1969

Today is the 4th of July, the day the United States of America celebrates its independence. It’s a unique and beautiful country, and I’m glad I had the good fortune to be part of it.
For much of its history the country was a bit of a scientific backwater, contributing modestly to [...]

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A couple days before I started teaching recitation sessions for Physics 208 (the E&M half of calc-based intro physics) this summer, I found out that in fact I was not teaching the second summer session, I’m teaching for the second half of the full summer session. Turns out there is a difference! For [...]

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