April 17, 2007
Cars that did not work
and did work.
Ways to push
that work.
Build and test for free wheeling in the air before trying on the ground.
Three are fun because bumping one can push the third.
Another way to put on wheels.
Note that this activity is very hard on hubs.
The distance a launcher would work was measured in inches
in the room.
In the hall it was easy to measure in feet.
