# Category Archives: math

## Constraint forces for path in 3D

This is a post mostly for my future self. What got me thinking about it was this comment about my planetary tunnels post: which is actually referring to a really old post of mine about how to dig a well. … Continue reading

## Does the hoop hop?

I greatly enjoyed this recent video from StandUpMaths: The set up is a hoop with a mass attached at one point. It’s rough so it rolls without slipping. It’s released with some angular momentum with the extra mass starting at … Continue reading

Posted in general physics, math, mathematica, physics | 1 Comment

## Creating bike routes with python

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

## Gabriel’s Horn (guest post)

Last week I was intrigued by this post: I asked, on Facebook, whether filling it with paint would essentially be painting it on the inside and I had a suspicion that my good friend Art Guetter (Professor of Mathematics at … Continue reading

Posted in guest post, math | 1 Comment

## What’s my 30 mile cycle limit?

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

## Brachistochrone for rolling things

The Brachistochrone curve is the shape of a wire for beads to slide down (friction free) to get from point A to point B the fastest. Note that since I used the word “down” there I’m implying this happens in … Continue reading

Posted in math, mathematica, physics, teaching | 3 Comments

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

## What are integers

This morning over the breakfast table my family had a great conversation about integers It started when my youngest, L (5th grade), talked about his math test tomorrow. He said the whole chapter was easy and that he wasn’t worried … Continue reading

Posted in math, parenting | 4 Comments

## Propellers with rolling shutter

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

## Best bingo board

My son is in the third grade and his math homework is to play games. The other night we played one that really got me thinking. Each player makes a 4×4 board and puts in any even number between 8 … Continue reading

Posted in fun, math, mathematica, parenting, Uncategorized | 9 Comments