Question

An earthquake generates three kinds of waves: surface waves (L waves), which are the slowest and weakest; shear (S) waves, which are transverse waves and carry most of the energy; and pressure (P) waves, which are longitudinal waves and travel the fastest. The speed of P waves is approximately 7.0 km/s, and that of S waves is about 4.0 km/s. Animals seem to feel the P waves. If a dog senses the arrival of P waves and starts barking 23.3 s before an earthquake is felt by humans, approximately how far is the dog from the earthquake’s epicenter?
drwls
Review this answer and use the same approach. Note that one number was changed.
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