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DCS# 8B40.30NWU# D-24 Location:    back corner
title: Ball on a Membrane
aka: membrane table

A membrane is stretched by a weight in the center, causing a depression that approximates a gravity well.  Small balls can be put into "orbit" given the right initial velocity.
The first version pictured is quite large, a small trampoline using a 32 lb weight for the dimple.
The second version is for use on an overhead projector or a camera projection system and uses small ball bearings.
The third version is inbetween the first two in size.

    Would this work on the moon? (ie. in lower g?)
     What does the central force depend on?
pix of set upoverhead version