Active+Learning+Investigation

=** Active Learning Investigation ** =

=PHYSICS MOBILE PROJECT – Rotational Equilibrium=

Physics or Physical Science, grades 9-12
 * CLASS/GRADE LEVEL: **

60 – 90 minutes
 * TIME: **

Scissors, twine, sticks, scale, tape, objects to hang, rulers, calculators.
 * MATERIALS: **

Design and construct an art mobile; using physics to calculate the mobile's rotational equilibrium.
 * OBJECTIVE: **
 * EALR 9-12 INQA Question ** Scientists //generate// and //evaluate questions// to investigate the //natural world//.

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.
 * BACKGROUND: **

1. Construct a hanging mobile having a minimum of **three freely-swinging horizontal arms**. 2. Select the hanging items for the mobile. 3. Sketch the general plan of your mobile. 4. Construct your actual mobile. You are likely to achieve the best results by **starting with the lowest level** and working upward. 5. Measure the **mass, and lever arm of each element** in the mobile and record your values. 7. On graph paper make a drawn-to-scale **“blueprint”** of your mobile in the form of a diagram indicating the actual lengths, positions of all strings, pivots and elements with the forces clearly labeled. 8. ** Calculate ** the net torque. 9. Hang your mobile from the ceiling in the classroom. 10. Hand in, along with your mobile, your “blueprint,” your calculations, and your measured data.
 * DIRECTIONS **

HINTS

 * Use objects of moderate mass. (less than 500g)
 * Do not use fragile or expensive objects.
 * Make the mobile simple, but large.
 * Be creative.
 * Plan ahead! Calculate carefully and accurately.
 * Ask yourself: Would I hang this mobile above a baby? (do not hang dangerous objects)


 * ASSESSMENT**
 * Completed mobile
 * Blueprints that match mobile
 * Calculations of torque
 * Participation in class