An Assessment of Hillslope Stability Using the Factor of Safety part of Quantitative Skills:Activity Collection
Laura Moore, University of North Carolina at Chapel Hill
In this homework assignment students are asked to consider the balance of forces on a hill slope using the Factor of Safety.

Atmospheric Vertical Structure and the First Law of Thermodynamics part of Quantitative Skills:Activity Collection
Anthony Hansen, Saint Cloud State University
This set of homework problems is intended to help students begin to discover the importance and utility of conservation principles derived from the First Law of Thermodynamics and provide a first step in evolving from the p-V diagrams the students have seen in their physics coursework toward the thermodynamic diagrams used in meteorology.

Three-Point Problem by Simultaneous Linear Equations part of Quantitative Skills:Activity Collection
William Frangos, James Madison University
Students are introduced to the use of linear algebra in an intuitive and accessible way, through classroom activity and homework set. The familiar three-point problem is cast in terms of three dimensional analytic geometry, fostering understanding of mathematical models for simple geometric forms.

Modeling the interior of the Earth using Seismic Waves part of Quantitative Skills:Activity Collection
Eric Baer, Highline Community College
Students use a variety of tools to explore the interior of the Earth in this inquiry activity.

Radioactive Decay and Geochronology part of Quantitative Skills:Activity Collection
Kirsten Menking, Vassar College
Students create a STELLA model of the radioactive decay process.

Illustrating Hillslope Diffusion with Physical and Numerical Models part of Quantitative Skills:Activity Collection
Gregory Hancock, College of William and Mary
This problem illustrates how numerical theories are developed, how we might test this theory with an analog model, and how numerical models are constructed and the limitations of numerical modeling.

Mid-level spreadsheeting and complex modeling of real-world scarp evolution part of Quantitative Skills:Activity Collection
William Locke, Montana State University-Bozeman
This exercise is a second or familiarization exercise in spreadsheeting, but is also a mathematical model for slope evolution. It uses the concept of "erosivity" (generally, the relative ratio of driving and resisting forces) and slope angle to reshape an initial topography. Finally, it asks the students themselves to come up with a real-world situation worth modeling.

Demonstration of radioactive decay using pennies part of Quantitative Skills:Activity Collection
Jennifer Wenner, University of Wisconsin-Oshkosh
A demonstration (with full class participation) to illustrate radioactive decay by flipping coins. Shows students visually the concepts of exponential decay, half-life and randomness. Works best in large classes -- the more people, the better.

Back-of-the-Envelope Calculations: Rate of Lava Flow part of Quantitative Skills:Activity Collection
Barb Tewksbury, Hamilton College
Question In 1983, an eruption began at Kilauea Volcano in Hawaii that has proved to be the largest and longest-lived eruption since records began in 1823. Lava has poured out of the volcano at an average rate of ...

Back-of-the-Envelope Calculations: Percentage of Copper in Ore part of Quantitative Skills:Activity Collection
Barb Tewksbury, Hamilton College
Question Suppose that you are building a new house. It will take about 90 kg (198 pounds) of copper to do the electrical wiring. In order to get the copper in the first place, someone needs to mine solid rock that ...