Question

Use the Travel Time function of the Interactivity to find the distance between each of your cities (their respective seismometers) and the epicenter of the earthquake. Compare the S–P values with the distance (km) values. Which of the following are correct?

A. The longer the S- and P-waves travel, the farther apart their wave fronts are in kilometers.
B. The shorter the time interval is between the arrival of the S- and the P-waves, the farther the seismometer is from the epicenter.
C. The smaller the S–P value is, the farther the seismometer is located from the epicenter.
D. The larger the S–P value is, the farther the seismometer is located from the epicenter.
E. The farther the epicenter is, the greater the time difference in the arrival of the P- and S-waves at a seismometer.

Answer 1

The distance to the epicenter of an earthquake can be determined by comparing the arrival times of S- and P-waves. The longer the waves travel, the farther apart their wave fronts are in kilometers. The shorter the time interval between the arrival of the S- and P-waves, the farther the seismometer is from the epicenter.

Step-by-step explanation:

The distance to the epicenter of an earthquake can be determined by comparing the arrival times of S- and P-waves, which travel at different speeds. The S-wave travels at 4.00 km/s and the P-wave travels at 7.20 km/s. By measuring the time difference between the arrival of the P-wave and the S-wave, the distance to the epicenter can be calculated.

The correct statements are:

1. The longer the S- and P-waves travel, the farther apart their wavefronts are in kilometers. The longer the travel distance, the greater the time difference between the arrival of the P-wave and the S-wave, indicating a farther distance from the epicenter.
2. The shorter the time interval is between the arrival of the S- and the P-waves, the farther the seismometer is from the epicenter. A shorter time interval between the arrival of the P-wave and the S-wave indicates a closer distance to the epicenter.
3. The larger the S–P value is, the farther the seismometer is located from the epicenter. The S–P value represents the time difference between the arrival of the P-wave and the S-wave, and a larger value indicates a farther distance from the epicenter.

Answer 2

The correct options are;

A. The longer the S- and P-waves travel, the farther apart their wave fronts are in kilometers.

D. The larger the S–P value is, the farther the seismometer is located from the epicenter.

E. The farther the epicenter is, the greater the time difference in the arrival of the P- and S-waves at a seismometer.

Step-by-step explanation:

Analyzing each of the statements, we have;

A. A P wave travels much faster than an S wave and a S wave can travel only through solid rock.

Therefore, A. the longer the S and P waves travel, the farther apart their wave fronts are in kilometers is correct

B. A P wave travels much faster than an S wave therefore, B is not correct as the epicenter and seismometer are two points separated by a distance which if the distance increases, the time interval between the arrival of the P and S wave increases

C. For similar reason, C is not correct

D. As the P wave travels much faster than an S wave, D is correct

E. Similarly, E. is correct, due to the difference in speed of the S and P waves