Category Archives: fun

Rolling without slipping on curved surfaces

Posted on December 31, 2022 by Andy Rundquist

I’ve been trying to see if I can model balls rolling on curved surfaces and I think I’ve cracked it. Here’s a teaser to get you interested: What you see is a sphere rolling on a curved surface. The blue … Continue reading →

Posted in fun, general physics, mathematica, physics | Leave a comment

Creating bike routes with python

Posted on October 30, 2022 by Andy Rundquist

This weekend my goal was to ride 50 miles to and from my house. In my last post I showed four ways to find where I could get to for a certain distance, but I really hate “there and back” … Continue reading →

Posted in fun, math, programming, technology | Leave a comment

What’s my 30 mile cycle limit?

Posted on October 4, 2022 by Andy Rundquist

UPDATED WITH 4th APPROXIMATION! Last weekend I went hammock camping by towing all my gear behind my bike. I loved it and now I’m interested in finding other adventures that won’t tax me too much. I really think that, for … Continue reading →

Posted in fun, math, mathematica, technology | 6 Comments

License plate math game

Posted on August 27, 2021 by Andy Rundquist

I do lots of things while I ride my bike to work to pass the time. Recently I’ve invented this game (surely others have too): Pick a target integer (I start at zero and move up by one in each … Continue reading →

Posted in fun, math | 2 Comments

One die to rule them all

Posted on January 16, 2020 by Andy Rundquist

For a number of years I’ve been working on finding ways to turn what looks like an unfair die to a fair one (see these posts). Recently I’ve made a lot of progress. This post shows how I’ve turned a … Continue reading →

Posted in fun, mathematica, physics, research | 4 Comments

Doppler Drum Corps

Posted on April 7, 2019 by Andy Rundquist

One of my favorite oral exam questions to give students in introductory physics classes is to ask them whether marching bands should worry about tuning because of the Doppler Effect (lots of details below but the short version: if there’s … Continue reading →

Posted in fun, general physics, mathematica, parenting, physics | 6 Comments

Stable, asymmetric dice

Posted on October 12, 2018 by Andy Rundquist

A while ago I set about trying to find asymmetric dice that might be fair. I’ve put a lot more work into it, but mostly because there’s been a lot of frustrating interesting tangents. Here’s the main thrust of the … Continue reading →

Posted in fun, mathematica, physics | 6 Comments

Fair Asymmetric Dice, getting there

Posted on April 29, 2018 by Andy Rundquist

Ever since my son and I worked on whether different types of 20-sided dice were fair I’ve been thinking about whether there might be some oddly shaped dice that could still be fair.  I’ve watched these three numberphile videos and I’ve looked … Continue reading →

Posted in fun, mathematica, physics | 7 Comments

No connections

Posted on January 11, 2018 by Andy Rundquist

Driving home today I heard a great story on NPR. I liked it so much that I thought I’d put it here to remind myself about it. I might have forgotten some of the details, but I think I still … Continue reading →

Posted in fun, teaching, technology | 1 Comment

Propellers with rolling shutter

Posted on July 22, 2017 by Andy Rundquist

I really loved Smarter Every Day’s cool video about propellers shot by digital video cameras: I especially like how he stuck with it over several years! I liked the explanation a lot about why the propellers take on such weird … Continue reading →

Posted in fun, math, mathematica, physics, Uncategorized | 1 Comment