An earthquake generates a primary seismic wave (P‑wave) that travels at a speed of 6.0 km/s. If the source of the quake is 30 km deep below the Earth's surface, how long does it take for the P‑wave to reach the surface?
Answer
5 seconds
The correct answer is 5 seconds — State the travel time as 5 seconds.
Step-by-step solution
- Define the distance the wave travels: 30 km.
- Use the formula for time: (t = \frac{d}{v}).
- Substitute (d = 30) km and (v = 6) km/s.
- Calculate (t = \frac{30}{6} = 5) seconds.
- State the travel time as 5 seconds.
Common mistake: Mixing up units or forgetting to divide distance by velocity
Concept tested: Travel time of seismic waves
Published · How this solution was prepared and checked
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