# Avalanche Design

This simulation is a model of how avalanches occur. There is a mountain slope with mud particles piled up. Each of the mud particles computes the pressure acting on it, which is a function of the weight of the particles piled up on top of it. This pressure is visualized by mapping its value to a color. If this pressure is more than what the current level of friction can hold, the particles start moving down the hill. The friction can decrease if rain pours down for example, and the wet mud particles have less cohesion with each other.

• Science

## Explorations

Create a mud slide on Monte Diabolo in Costa Rica!

• Open the "Monte Diabolo" worksheet in AgentSheets or in the Java applet and run it. Alternatively, you can define your own landscapes using the Ground agent. Please note that the ground agents are invisible, so that the background can be seen.
• Select the Mud-Particle agent (the black square) in the Gallery.
• Use the Draw Rectangle tool to drop a bunch of mud particles on the mountain slope and let it settle down.
• Click on the tiny + agent with the Hand tool to increase the friction of the Mud-Particles
• Click on the tiny - agent to decrease the friction. The + and - are hard to see, but they are somewhere in the clouds.
• Observe the effects on the variation in friction. How low does it get before the mud slide occurs? Hint: you can use decimal numbers for Friction values as well.
• Add a Sonifier in your worksheet to hear the sound of the mud slide.
• Create a new Rain agent that drops from the sky and decreases the friction as it sips into the mud particles.

## Standards

• Creativity and Innovation:
• use models and simulations to explore complex systems and issues
• Science and Technology Standards:
• Understandings about science and technology
• Abilities of technological design
• Content Standards: Physical Science
• gravity, particle motion, friction (Motion and Forces)
• properties and changes of properties in matter
• Science as Inquiry Standards:
• Abilities necessary to do scientific inquiry

## Acknowledgements

• Simulation built by Alexander Repenning in collaboration with people from the University of Costa Rica.