Question

When earthquakes occur, seismic waves are sent through the Earth. The two most common types of seismic waves are P waves and S waves. Based on the graph, what is true about P waves and S waves?

a) They travel at the same speed through the Earth.
b) They travel at different speeds through the Earth.
c) They both travel faster than 7,000 miles per minute.
d) They both travel slower than 1,000 miles per hour.

Answer 1

P waves and S waves travel at different speeds through the Earth, with P waves being faster and using their arrival times can help calculate the epicenter of an earthquake.

Step-by-step explanation:

When earthquakes occur, seismic waves such as P waves and S waves are sent through the Earth. Based on the information provided, the main answer to the question about P waves and S waves is that (b) They travel at different speeds through the Earth. P waves are pressure or longitudinal waves that travel faster in rigid material, typically between 4 to 7 km/s, while S waves are shear or transverse waves with speeds ranging from 2 to 5 km/s. The conclusion that can be drawn is that, since P waves are faster, they are the first to be detected by seismographs after an earthquake, and the time difference between the arrival of P waves and S waves is used to calculate the distance to the earthquake's epicenter.