Final answer:
The lag time at 2,000 km from the earthquake's epicenter is 30 s.
Step-by-step explanation:
The lag time at 2,000 km from the earthquake's epicenter can be calculated using the formula:
Lag Time = Distance / Wave Speed
In this case, we need to determine the wave speed.
We know that the S-wave travels at 2 km/s and the P-wave travels at 6 km/s.
The time difference between the two waves recorded at the certain point is given as 10 seconds.
Let's calculate the distance:
For the S-wave: Distance = S-wave Speed x Lag Time = 2 km/s x 10 s = 20 km
For the P-wave: Distance = P-wave Speed x Lag Time = 6 km/s x 10 s = 60 km
Since the lag time at 2,000 km is beyond the distance recorded, we can estimate the lag time by finding the ratio between the distances and applying it to the given lag time.
The ratio of the given distances is 60 km / 20 km = 3.
Therefore, the lag time at 2,000 km is:
Lag Time = Lag Time x Ratio = 10 s x 3 = 30 s
So therefore the lag time at 2,000 km from the earthquake's epicenter is 30 s.