Category: Education

Waves: Moving Without Going Anywhere

At the tail end of Tuesday’s post about wind and temperature, I asked a “vaguely related fun bonus question:” If the air molecules that surround us are moving at 500 m/s anyway, why isn’t the speed of sound more like 500 m/s than 300 m/s? This is another one that people are sometimes surprised by.… Continue reading Waves: Moving Without Going Anywhere

Wind and Temperature: Why Doesn’t Windy Equal Hot?

I got forwarded a physics question last night asking about the connection between wind and temperature, which I’ll paraphrase as: Temperature is related to the motion of the atoms and molecules making a substance up, with faster motion corresponding to higher temperature. So why does it feel warmer when the air is still and why… Continue reading Wind and Temperature: Why Doesn’t Windy Equal Hot?

Synchronicity and “Administrative Bloat”

At Inside Higher Ed this morning, they have a news squib about a new report blaming the high cost of college on “administrative bloat.” Coincidentally, the Dean Dad has a post pre-emptively responding to this in the course of arguing with a different group: In terms of administration, what would you cut? Should we stop… Continue reading Synchronicity and “Administrative Bloat”

Algebra and Circuit Breakers

A couple of “kids these days are bad at math” stories crossed my feed reader last week, first a New York Times blog post about remedial math, then a Cocktail Party Physics post on confusion about equals signs. The first was brought to my attention via a locked LiveJournal post taking the obligatory “Who cares… Continue reading Algebra and Circuit Breakers

What Do You Need to Make Cold Atoms? Appendix: “No-Laser” Methods

Last week’s series of posts on the hardware needed for laser cooling and trapping experiments dealt specifically with laser-cooling type experiments. It’s possible, though, to make cold atoms without using laser cooling, using a number of techniques I described in two posts back in January. Those didn’t go into the hardware required, though, so what’s… Continue reading What Do You Need to Make Cold Atoms? Appendix: “No-Laser” Methods

What Do You Need to Make Cold Atoms? Part 1: Vacuum Hardware

Over in the reader request thread, Richard asks for experimental details: I’d be interested in (probably a series) of posts on how people practically actually do cold atoms experiments because I don’t really know. I needed to take some new publicity photos of the lab anyway, so this is a good excuse to bust out… Continue reading What Do You Need to Make Cold Atoms? Part 1: Vacuum Hardware

Cold Atoms and Cooper Pairs

So, last week, I talked about how superconductors work, and I have in the past talked about the idea of making cold atoms look like electrons. And obvious question, then, whould be: Do cold atoms systems allow us to learn anything about superconductivity? The answer here is, unfortunately, “Yes and no.” That’s pretty weaselly, dude.… Continue reading Cold Atoms and Cooper Pairs

What’s a Photon, and How Do We Know they Exist?

A reader emailed me with a few questions regarding How to Teach Physics to Your Dog, one of which is too good not to turn into a blog post: What is a photon from an experimental perspective?… Could you perhaps provide me with a reference that discusses some experiments and these definitional issues? The short… Continue reading What’s a Photon, and How Do We Know they Exist?

Reader Request: What’s the Matter with Stat Mech?

On the reader request thread, commenter Brad had several questions; one led to yesterday’s post about superconductors, another is a critical issue in pedagogy: Finally, why did all of my stat[istical] mech[anics] courses suck? Statistical Mechanics is the branch of physics that deals with building up macroscopic thermal properties of materials from a microscopic model… Continue reading Reader Request: What’s the Matter with Stat Mech?