Seismographs can record two types of wave energy (P waves and S waves) that travel through the Earth after an earthquake. Traveling through granite, P waves travel approximately 5 km/sec and S waves travel approximately 3 km/sec. If a geologist working at a seismic station measures a time difference of 40 sec between an earthquake's P waves and S waves, how far from the epicenter of the earthquake is the station?

Question

anonymous · Answer

do you have the answer ?

anonymous · Answer

The answer is 300 km. But I don't know how to reach that conclusion.

perl · Answer

P waves are longitudinal , and S waves are transverse waves. P waves travel faster (they act like sound waves, or bumper cars)

perl · Answer

there is a graph here on this page http://www.colorado.edu/physics/phys2900/homepages/Marianne.Hogan/graphs.html

anonymous · Answer

Ok, but how do I reach the answer. To figure out how far the epicenter is from the station?

perl · Answer

http://regentsprep.org/regents/earthsci/eqwaves.htm

anonymous · Answer

isnt the ans 120 ?

anonymous · Answer

In the book the answer is 300km.

perl · Answer

I think you can use an equation here http://www.data.scec.org/Module/sec3pg13.html

perl · Answer

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