Page 46 - Laboratory Manual in Physical Geology

2. Recall that Earth’s actual average radius is 6371 km (6,371,000 meters) and that the radius of the basketball is only

119 mm (0.119 meters). Calculate the fractional scale (show your work) and ratio scale of the basketball model.
Fractional scale: Ratio scale:

B. MODELING LANDSLIDE HAZARDS
1. Place a ruler flat on a table in front of you. Place a coin in the center of the ruler. What happens if you lift one end of

the ruler?

2. The coin did not slide off of the ruler at the very second you started to lift one end of the ruler. Why?

3. Why did the coin start sliding when it did?

4. REFLECT & DISCUSS Landslides are sudden downslope movements of rock, soil, and mud that occur in every country
of the world. The U.S. Geological Survey warns that landslides are a major geologic hazard because they happen in all
50 states and U.S. territories and cause $1–2 billion in damages and more than 25 fatalities in the U.S. on average each
year. Describe below how you would modify your ruler and coin model and use it to study what factors can trigger a
landslide?

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