Elastic Rebound Demonstration using a Yardstick
Science
Demonstrating Elastic Rebound using a Yardstick
Now let's look at a mechanical analog here. Brittle material. What do you mean by brittle if we say that the lithosphere is rigid and brittle material brittle implying that it's capable of fracturing and therefore it's capable of producing earthquakes? So an elastic material, what you mean by that is you can bend an elastic material, but then if you take the forces off, it'll go right back to its original configuration.
So I can bend the yardstick here, bring it right back to zero by taking the forces off. However, if I get two energetic with this, if I put too much force on this yardstick, we know that it's a brittle material, and it will eventually break. It will fracture. So you can bend it, you can actually do things in class where you can draw an arc on the black border or a set of arcs and maybe number them. And you can show you can demonstrate why it's difficult to predict earthquakes by simply asking the question at what art is this rental material, this yardstick going to break. Make people commit themselves and vote before you bend the yardstick. So you can bend the yardstick a little bit, bang, goes right back. Perfectly elastic material.
Now get energetic with it. Boom, brakes. That's an earthquake. We just produced a brittle fracture. We produce sound in the room that was elastic waves going through the air, and so we have generated for ourselves an earthquake. So brittle material, the lithosphere is relatively cold. It's rigid. It's brittle, therefore it's capable of generating earthquakes.