PROJECT OBJECTIVE:
Design and construct an art mobile around a general theme using physics to calculate the
mobile's translational and rotational equilibrium.
ART BACKGROUND:
Alexander "Sandy" Calder (1898-1976) was an artistic pioneer who created the art form called the
mobile. By the early 1970s, Calder's mobiles were famous worldwide. His sculptures ranged in
size from the monumental
to jewelry-sized.
"I used to begin with fairly complete drawings, but now I start by cutting out a lot of shapes....
Some I keep because they're pleasing or dynamic. Some are bits I just happen to find. Then I
arrange them, like papier collé, on a table, and "paint" them -- that is, arrange them, with wires
between the pieces if it's to be a mobile, for the overall pattern. Finally I cut some more of them
with my shears, calculating for balance this time."
- Alexander Calder on building a mobile, from Calder's Universe, 1976.
OBJECTIVE
To construct a hanging mobile having a minimum of three freely
swinging horizontal arms using an artistic general theme.
DIRECTIONS
1. Sketch the general plan of your mobile. Keep this sketch and all
of your work in your Projects notebook.
4. Find the mass of each element in the mobile including the rods.
5. Determine the position of each support string. Strings may not
be attached at the center of mass of a support.
6. Complete the mobile “blueprint” indicating the actual lengths,
positions of all strings, pivots and elements with the forces
clearly labeled.
7. Demonstrate by neat calculations that translational and
rotational equilibrium exists.
8. Construct your actual mobile.
HINTS
1. You are likely to achieve the best results by starting
with the lowest level and working upward.
2. Use objects of moderate mass. Do not use fragile
or expensive objects. Handmade objects are
acceptable.
3. Make the mobile simple, but visually strong. Your
mobile must be no larger than 50 cm wide, 50 cm
deep and 100 cm tall
4. Be creative!
5. Plan ahead! Calculate carefully and accurately.
PROJECT ASSESSMENT
I. Mobile 10pts
- 5pts Neat and sturdy construction and assembly.
- 5pts Well balanced.
- 10-20pts Three or more levels or extra tiers. (BONUS 5pts per tier).
II. Calculations and write up 20pts
Calculations:
-3pts Includes 3 formulas: Torque Equillibrium, Rotational Inertia and Centripetal Force
-5pts 1paragraph Explanation of how the formulas relate to parts of the mobile.
-12pts Comprehensive, neat, accurate and easy-to-follow with all calculations shown for every
object.
Show all your work including both conditions for equilibrium
and the solved equations. HINT (Big chart like the Rube Goldberg Machine is perfect)
III. Blueprint 5pts
- Neat, properly labeled and to scale.