Physics 122 Week 5
Pendula
Pendula
Use these two pendula to lead your students into an investigation as to what affect's a pendulum's period. Both bob's have a different mass, and you can wrap a pendulum around the stand to change its length.
Large Pendulum
This is another simple pendulum, just larger! To change pendulum length just wrap the string around the stand. **Please do not detach the stopping bar, just slide it out of the way**
Variable "g" Pendulum
By rotating the plane of oscillation, you change gravity's restorative component on the pendulum. Use this demonstration to show a pendulum's period dependency on gravity.
Pendulum Wave
A set of pendulums with differing lengths are set into harmonic motion. Their differing periods create a predictable and repeatable pattern. There are some amazing YouTube videos of different versions in UV light.
Simple vs Physical Pendula
Both pendula are the same mass and length. Show students that the true influence on period is the object's moment of Inertia with this demonstration.
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Oscillatory Motion
Periodic Motion Devices
A Ball in a Bowl, Winding Spool, and Maxwell’s Wheel all undergo oscillatory periodic motion. Set them in motion and ask your students what they share in common to begin discussing periodic motion.
Masses on Springs
Each spring has a different spring constant so that you can show your students how the "k value" influences a mass-spring system's period. Can you and your students figure out how much mass to add on a spring such that two oscillate at the same period?
Linear Oscillator
The cart oscillates back and forth between two springs. There are accompanying masses that slot into the cart. If you can add them to the cart while it's at a maximum you can change the period without adding any extra force.
Simple Harmonic Motion and Circular Motion
An edge on projection of an object in circular motion results in simple harmonic motion. This demonstration puts a simple harmonic oscillator next to an object in uniform circular motion. When comparing their shadows we see they behave the same!
Damped Oscillator
When you add some resistance to a vibrating hacksaw blade you can can clearly see a damped oscillation. Vary the card size to change the damping constant.