1. Simple Harmonic Motion and Harmonic Oscillator Systems
4/27/2017
Experiment 7
Simple Harmonic Motion and Harmonic Oscillator Systems

2. Simple Harmonic Motion
Common physical model
springs, flexing beams,
pendulums, laser light,
forces between particles
first approximation for any
bound system or anything that
oscillates

3. Simple Harmonic Motion
SHM
= sinusoidal oscillations
Period for the simple pendulum
Period for the mass on the end of a spring

4. Part 1. Mass at the end of the spring
Measure the spring constant using Hooke’s Law: F(x)=-kx Measure period (consider at least 10 oscillations) and compare it with the period calculated by equation:
*Change: Use 50 g brass weight pan with 50g slotted mass

5. Part 2. Simple Pendulum
Measure period using the sine fit (~10 degrees amplitude!). Calculate period by equation:
Compare calculated and measured periods.

6. Also:
- Print out the window with three plots:
Label physically significant points on all three of them! How does period depend on: Mass? Length? Amplitude?

7. Part 3. Period of Loaded Cantilever Support
SONAR
MASS
Part 3. Period of Loaded Cantilever Support
Paper clip attaches to
side of tongue depressor
Not front end!
*Change: Use 50 g brass weight pan with 50g slotted mass
Push on tongue depressor with rubber tipped force probe to measure spring constant for cantilever. Make the cantilever oscillate and measure the cantilever period using sine fit.

8. Cantilever continued
Calculate the cantilever’s period by the equation for the mass on the end of the spring (using k you just found and m)
How does it compare to the experimental result?
Is the harmonic oscillator a good model for the cantilever?

9. Reminders Your Lab report for this experiment
Is turned in at the end of this session!
Best Wishes on all your exams and paper!