Direct Measurement Videos > Video Library > SHM Trio 1

Three Objects in Simple Harmonic Motion


Pick a Video:

All three of these objects move in very similar ways. They look almost as though they are attached or coupled in some way, but they are not. Students can use this video to observe the similarity between these seemingly unrelated types of motion.

This video suggests that if we can build tools to analyze one of these situations, we can use them to describe the other situations.

This video can also be downloaded for use in LoggerPro, Tracker, or other video analysis software to make and explore motion graphs.


Instructor Note

When teaching with this video, direct students to the student video library, which provides student access to all videos without links to instructor materials and solutions.

View the video directly in your web browser using this link to the DMV Player

For use in LoggerPro, Tracker, or other video analysis, download the file: download (MP4 Video 5.6MB Mar14 15)

Teaching Materials

The instructional goal of this video is for students to be able to see the similarities between the motion of three seemingly unrelated types of motion: a spring oscillator, a simple pendulum, and an object moving in simple harmonic motion.

The pendulum string is attached just out of view above the video. The length of the pendulum can't be precisely measured. Other DMVs (in process summer 2015) will allow students to explore the relationship between the length of a pendulum and the period of oscillation.

The glider moves on a low-friction air track, pulled by two springs. At the mid-point of the motion, both springs pull equally, creating a balanced force. As the glider moves to the left, for example, the force from the left spring decreases and the force from the right spring increases. The glider experiences an unbalanced force to the right that increases the farther the glider moves to the left.

The rotating platform is attached to a record player, just barely visible at the bottom of the page. The yellow and blue marker allows students to consider the motion of a single point moving in circular motion.