Elastic Rebound Demonstration using a Yardstick

How is stress stored between tectonic plates?

Dr. Butler talks about elasticity and brittle material using a yardstick as a mechanical analog for the lithosphere. The yardstick is a brittle material that has elastic properties, yet, like the lithosphere, is capable of generating earthquakes.

The lithosphere is brittle yet elastic. A yardstick is also brittle yet elastic and both are capable of storing energy and rebounding elastically. Both are also cabable of breaking and generating earthquakes. This demo shows why it is difficult to predict earthquakes.

Video lecture of Dr. Robert Butler, University of Portland speaking to middle-school teachers.


Keypoints:

Discovery

  • What happens when stress is applied to brittle materials?
  • How can I use brittle material to demonstrate an earthquake?
  • What is “elastic rebound”?


Level: Novice

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