Study the image of a seismic graph.

Graph of P & S Wave Travel Times, showing Travel time in minutes across distance in kilometers for P and S waves. S wave starts at zero kilometers, zero minutes, and increases to 10,000 kilometers, 25 minutes. P wave starts at zero kilometers, zero minutes and increases to 10,000 kilometers, 13 minutes.

About how far does the S wave travel through Earth in 13 minutes?

2,000 km
4,000 km
6,000 km
8,000 km

1 answer

To determine how far the S wave travels in 13 minutes, we can refer to the information provided in the seismic graph for S waves.

From the description, we know that:

  • The S wave begins at zero kilometers and zero minutes and increases to 10,000 kilometers at 25 minutes.

We can calculate the slope of the line representing S waves:

  1. The S wave travels 10,000 kilometers in 25 minutes.

  2. The speed of the S wave can be calculated as:

    \[ \text{Speed of S wave} = \frac{10,000 \text{ km}}{25 \text{ minutes}} = 400 \text{ km/min} \]

  3. To find the distance traveled by the S wave in 13 minutes:

    \[ \text{Distance} = \text{Speed} \times \text{Time} = 400 \text{ km/min} \times 13 \text{ min} = 5,200 \text{ km} \]

Since none of the options match exactly with 5,200 kilometers, we need to identify the closest option. Here are the given choices:

  • 2,000 km
  • 4,000 km
  • 6,000 km
  • 8,000 km

The closest option to 5,200 km is 6,000 km. Therefore, based on the options provided, the best answer is:

6,000 km