Seismic waves

• What are the two types of seismic waves discussed in the video?

  P waves and S waves
• What type of wave are P waves and what can they travel through?

  P waves are longitudinal and can travel through both solids and liquids
• What type of wave are S waves and what can they travel through?

  S waves are transverse and only travel through solids
• How do the speeds of P waves compare to S waves?

  P waves are much faster than S waves
• How do scientists use seismic waves to understand the Earth's internal structure?

  By studying how the waves travel through the Earth
• What devices do seismologists use to detect seismic waves?

  Seismometers
• What do seismologists compare to understand the travel time of seismic waves?

  Their results with those of other seismologists around the world
• What happens to seismic waves when they reach a boundary between two different mediums?

  They can be reflected, absorbed, or transmitted
• What does refraction of seismic waves indicate?

  It indicates that waves change speed in mediums of different densities
• What occurs at the boundary between the mantle and the liquid outer core?

  There is a sudden change in density and direction of the wave
• How do waves behave as they pass through the liquid outer core?

  They are constantly being refracted and seem to curve
• How do waves behave in the mantle regarding density?

  Waves are generally refracted and seem to curve due to varying density
• What is the difference in behavior of P waves and S waves as they pass through the Earth's layers?

  P waves can travel through both solids and liquids, while S waves cannot travel through liquids
• What was one of the main clues that led scientists to discover the existence of a liquid outer core?

  S waves could not pass through the liquid outer core
• Why couldn't S waves be detected in certain regions during an earthquake?

  Because they cannot travel through the liquid outer core
• Where are P waves detected during an earthquake?

  P waves are detected almost everywhere
• What happens to waves that pass through the outer core during an earthquake?

  They are refracted downwards
• What is the main takeaway regarding how scientists discovered the Earth's internal structure?

  By measuring which types of waves could be detected at different places around the Earth
• What is the key difference between P waves and S waves in terms of their travel capabilities?

  P waves can travel through solids and liquids, while S waves can only travel through solids
• What are the characteristics of P waves and S waves?

  • P waves:
  • Longitudinal
  • Travel through solids and liquids
  • Faster than S waves
  • S waves:
  • Transverse
  • Only travel through solids
• How do seismic waves help in understanding the Earth's internal structure?

  • Seismic waves travel through different layers of the Earth
  • Their behavior at boundaries provides clues about density changes
  • Detection of P waves and S waves indicates solid and liquid layers