Speed Problems with Earthquake Waves Name ________________________ 1. Below is a graph of the 2 types of earthquake waves. Use it to fill out this table Time to get to 2,000 Km Relative Speed (faster/slower) Type of Wave (P/S) Amount of Shaking/Impact (More / Less) Curve A Curve B A B Time Minutes Distance 103 Kilometers 2. a.Based on the graph, how long did it take the S waves to get to 1,000 km? ______ b. Convert that time to seconds: c. Calculate the speed in km/sec for S waves: 3. a. Based on the graph, how long did it take the P waves to get 1,000 km? ______ b. Convert that time to seconds: c. Calculate the speed in km/sec for P waves: 4. A. Using those speeds how long would it take for an P wave to go 800. Km? B. Using those speeds how long would it take for an S wave to go 800. Km? C. At 800. Km how much time is there between the smaller P’s and the bigger S’s? How much warning would you have that a worse wave is coming? 5. A. Using those speeds how long would it take for an P wave to go 200. Km? B. Using those speeds how long would it take for an S wave to go 200. Km? C. How much warning would you have at 200. km that a worse wave is coming? 6. How much warning time do you think is needed to get people into safer situations? Suppose a p wave reached a seismographic station, triggered a signal to send an emergency alert to every local cell phone and then people got under their desks at school or pulled over if driving before the S waves hit. How much time do you think that process would take? 7. Based on your answers to 4 - 6 do you think a p wave based early detection system is feasible?