# 1-D Motion with a force in Scratch

I can’t remember how I found this, but [Scratch](http://scratch.mit.edu) is a graphical programming language developed at MIT. My kids love this. In order to make sure they don’t know more than I do, I created my own scratch program. I am sure someone from the scratch community will attack it for some reason, but I…

# Physics of Linerider IV: Friction?

Friction in Line Rider Is there friction in Line Rider? Does it function as physics would expect? To test this, I set up a simple track: ![Page 6 1](http://scienceblogs.com/dotphysics/wp-content/uploads/2008/09/page-6-1.jpg) Basically, a slope with a flat part to start with and to end with. Let me show you something simple before further analysis: ![Page 6 2](http://scienceblogs.com/dotphysics/wp-content/uploads/2008/09/page-6-2.jpg)…

# Physics of Linerider III: Air Resistance

There is no air resistance in line rider. Sorry to spoil the suspense. To test for the presence of an air resistance force, a track was created that let the rider fall. ![linerider air 1](http://scienceblogs.com/dotphysics/wp-content/uploads/2008/09/linerider-air-1.jpg) (note the markers on the side. These are used to keep track of how the origin is moving). Below is…

# Physics of Linerider Part II: Scale

Scale of the Line Rider First, we assume that the line rider is on Earth and for low speeds will have a free-falling acceleration of 9.8 m/s2. Next, an arbitrary distance is selected. In this case the length of the sled is chosen to be 1 LU (Linerider Unit). ![line rider](http://scienceblogs.com/dotphysics/wp-content/uploads/2008/09/line-rider.jpg) The goal will be…

# The Physics of Linerider

Part I: Introduction http://linerider.com is a flash “game” in which the user can create tracks. A rider is then allowed to slide down these tracks. If you have not played this, I recommend you DON’T play it. It is very addicting and can consume many hours of your time (hours you would otherwise spend on…