Demos: 1S-26 Vibrating Meter Sticks
Two identical meter sticks are clamped at the edge of a table with different lengths extended. The same weight is attached to the end of each meter stick which is then displaced a few centimeters and allowed to oscillate. The longer projection will have a longer period due to the larger rotational inertia about the clamp point.
Directions: Clamp the meter sticks in such a way that the projecting lengths are the same. Then shorten one of the projections little by little to observe the change in period. Then with the lengths the same, use different weights to show the inertia effect.
Suggestions for Presentation: Because this is, in fact, a physical pendulum, emphasize the nature of the restoring torques (tensions and compressions built up in the meter stick as it is flexed) and how the rate of oscillation is controlled by the rotational inertia. Refer to Demo 1J - 20 (Ball on Stick).
Applications: If the oscillations are fast enough, sound will be produced and this is the basis for sound production in the music box, where the length of the metal reed determines the pitch.