Periodic & Circular Motion: Harmonic Motion
Students will measure the period of oscillation of a mass on the end of a spring and compare the measured period to a theoretical value based on the mass and the spring constant.
Real time data collection enables students to lock in a one-to-one relationship between the data and the phenomena.
Lab Summary
In both Math and Science an understanding of harmonic behavior is fundamental.
Using a simple mass and spring, your students see the force plotted on their screen in real time. They can change the parameters of the system and compare the period of the resulting sinusoidal data with the theoretical value they calculate from the mass and spring constant.
This simple system is a great way to introduce the idea of a mathematical model to your students.
Theory
Simple Harmonic Motion occurs whenever a restoring force is proportional to an objects displacement from equilibrium. It is most often seen with pendulums, and in this case, masses suspended from a string. When the mass is released the force increases to its maximum value before it moves upward and gravity acts to bring it back down to complete the cycle. Plotting force (or position) over time gives a sinusoidal graph.
Downloads
- Download Free Lab (PDF, 272 KB) (271 KB, .pdf)
(student version)
Method
Use a Force Sensor to measure the force on a spring as a mass oscillates up and down on the end of the spring.
Here's What You Need
U.S. Educator prices shown.
Probeware
PASPORT Force Sensor (PS-2104) - $110
Designed to measure both pulling and pushing forces. Uses range from collisions to tug-of-war. For use with PASPORT Interfaces.
Xplorer GLX (PS-2002) - $349
The Xplorer GLX is a data collection, graphing, and analysis tool designed for science students and educators.
Other Products
Double Rod Clamp (3 pack) (ME-9873) - $18
Clamp holds two rods either parallel or perpendicular to one another.
Equal Length Spring Set (ME-8970) - $39
These springs appear to be the same except for their colors. But, when equal masses are hung on them, each stretches a different amount.
Ohaus Triple-Beam Balance (without Tare) (SE-8723) - $147
This Ohaus triple-beam mechanical balance (without tare) is accurate and easy to use. This balance has been a standard weighing instrument in student laboratories for decades.
Lab Manual
This activity is included in Physics with the Xplorer GLX (PS-2826), complete with Teacher Information pages, student instructions and handouts, and sample data for a total of 35 probeware-based labs. For your convenience, we offer bundles which provide the probeware necessary for the activities in the manual. For more information on these resources and bundles, click here.
