How to Make a Model of Gravity
- 1). Cut a length of nylon stocking about 12 inches long. Slit one side of the stocking and lay the nylon flat.
- 2). Take the lid off a shoebox and stretch the nylon over the top. Tape the sides to the box with duct tape, making the nylon snug. Do not overstretch the nylon and cause runs.
- 3). Lay the straight edge across the top of the nylon from one edge of the box to the opposite, and with the paintbrush create a thin, straight yellow line. Make parallel lines about 1/2 inch apart until the nylon is filled with lines. Let those dry, then turn the straight edge and create perpendicular lines 1/2 inch apart so the entire nylon is cross-hatched. Let dry.
- 4). Gather the nylon in the middle so that some of the parallel lines converge. Tie a small knot where you've gathered the nylon. Optionally, you can secure the gathering with a rubber band.
- 5). Make a small slit in the bottom of the shoebox. Push the knot of gathered nylon down to the bottom of the box and push the brad through the nylon and the slit in the box. Spread out the brass arms of the brad to hold the nylon in place.
- 6). Place a small "super ball" or rubber ball inside the concentric cone to represent a planet or other celestial object. Some of the lines you painted on the nylon should converge around the planet.
Source...