How do I figure out how far away an earthquake is in meters given the velocity of the P and S waves?
Feb 01, 2010
in
Earthquake Questions
The speed of longitudinal waves, called P waves, is 8000 m/s.
Transverse waves, called S waves, travel at a slower 4500 m/s . A seismograph records the two waves from a distant earthquake.
If the S wave arrives 2.0 min after the P wave, how far away was the earthquake?
If possible, I’d like the answer as well as an explanation of how to solve the problem so that I can work back through it again myself. Thanks!
Like this post? Subscribe to my RSS feed and get loads more!
One comment
kirchwey on February 1, 2010 at 9:00 am
ts = d/4500
tp = d/8000
ts-tp = 120 s = d/4500 – d/8000 = d(1/4500-1/8000) = 9.722222E-5*d
d = 120/9.7222E-5 = 1234286 m
Just a little algebra. Remember the trick that x/a ± x/b = x(1/a ± 1/b). It’s very useful.