The value of multi-modal trips

In transit lingo, “multi-modal” trips are those that use different modes to get to a destination. A common version is bike to bus/subway/rail, either taking the bike on the vehicle or locking it before one...

Drive 55 MPH on Spare the Air days

With the batch of Spare the Air days in the San Francisco Bay Area in the last few weeks, I came up with an idea that would probably save a lot more gas than trying...

“Progressive” thermostats to save energy

Sitting in my cold, air-conditioned classroom the last week, while it was 85-95ºF outside, a design for a new thermostat came to me. Currently, thermostats cool (or heat) a building to a desired temperature. My...

200 people can commute in:

Great poster from Seattle demonstrating the space it takes on a street to move 200 people in various modes.

Uprisings: The Whole Grain Bakers’ Book

Update: December 2010: I have created a web site, uprisingsbakersbook.org, where I’m adding recipes and other pages from the book. I’m working on permissions from the publisher and bakeries, so I’m starting with bakeries that...

The physics (and biology) of snake movement

Science Friday had a great piece on snakes slithering today. The main researcher in the video is Dr. David Hu from the Applied Mathematics Laboratory, Courant Institute of Mathematical Sciences, New York University, New York,...

The math in a hybrid car

For an end of the semester project in my physics classes, I posed the following question to my students: If you put 100,000 miles on a car, which is a better deal, a hybrid or...

Free shoppping?

It’s that time again. Time to wander the aisles of the college town “free stores.” These stores don’t pay rent, and the aisles move daily (if not hourly). The merchandise are the items the students...