Let’s work through the problem step by step.
We are looking at Figure 7-6, which shows seismograms from three different stations: Denver, Houston, and Miami. Each seismogram has two important lines:
- The first wiggly line is the
P wave (primary wave) — it arrives first.
- The second wiggly line is the
S wave (secondary wave) — it arrives later.
The question asks:
1. What is the time separation between the vertical lines in Figure 7-6?
Looking at the figure, each station’s seismogram has a scale below it that says “Minutes” and shows marks labeled 0, 5, 10, 15, etc. These are the vertical lines we’re being asked about.
Between any two consecutive vertical lines (like from 0 to 5, or 5 to 10), the time difference is:
> 5 minutes - 0 minutes =
5 minutes
So, the time separation between each vertical line is
5 minutes.
This is also confirmed by the note under the figure:
*“Please note that the lines on this chart are shown as: Hours : Minutes : Seconds”*
But looking at the actual labels on the chart (0, 5, 10, 15), they represent
minutes, not hours or seconds — so each tick mark is 5 minutes apart.
✔ Final Answer:
5 minutes
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Final Answer:
5 minutes
Parent Tip: Review the logic above to help your child master the concept of earthquake epicenter worksheet.
