Understanding Earthquake Epicenter Calculation

What are the two versions of the activity mentioned in the introduction?

• A complex lag time graph and a distance graph

• A simplified lag time graph and a complex lag time graph

• A simplified lag time graph and an S and P lag time graph

• An S and P lag time graph and a distance graph

In the easier version, what is the first step students must take?

• Determine the time of origin of the earthquake

• Use a triangulation compass

• Identify the arrival times of P and S waves in each city

• Calculate the distance to the epicenter

How do students find the distance to the epicenter in the easier version?

• By measuring the distance on a map

• By using a triangulation compass

• By calculating the time of origin

• By looking up the lag time on a graph

What additional information can be determined using the harder version of the activity?

• The depth of the earthquake

• The exact location of the epicenter

• The time of origin of the earthquake

• The magnitude of the earthquake

What tool is recommended for finding the distance to the epicenter in the harder version?

• A sticky note or scrap paper

• A ruler

• A protractor

• A calculator

What is the purpose of using a triangulation compass in the activity?

• To measure the magnitude of the earthquake

• To find the epicenter by drawing circles around cities

• To calculate the distance between cities

• To determine the exact time of the earthquake

How do students ensure they have the correct distance to the epicenter?

• By using the same version of the activity for all students

• By using a different graph for each city

• By checking that the time of origin is consistent across cities

• By measuring the distance manually

What is a key point to remember when using the triangulation compass?

• Use the outside arrow for all measurements

• Always use the inside arrow for accuracy

• Tighten the knob as much as possible

• Ensure the compass is not too tight to avoid breaking it

What is the final step in determining the epicenter using the triangulation method?

• Calculating the time of origin

• Drawing circles around each city

• Finding where all three circles intersect

• Measuring the distance between the circles

What is emphasized as important for mastering the activity?

• Practicing the activity multiple times

• Memorizing the steps

• Using a digital tool for accuracy

• Using the same version for all students