SOLUTION: 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
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Question 1138286: 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? Answer by ikleyn(52776) (Show Source):
Let d be the distance from the epicenter of the earthquake to the station (in kilometers).
For P-wave, the traveling time is seconds.
For S-wave, the traveling time is seconds.
The difference is
- = 40 seconds.
It is your "time" equation.
To solve it, multiply all terms by 15 = 3*5. You will get
5d - 3d = 15*40
2d = 600
d = 300 kilometers.
ANSWER. The distance from the epicenter of the earthquake to the station is 300 kilometers.
Solved.
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From my post, lean on how to write, to solve and to use a "time" equation.
