The earliest scientists first observed the waves that earthquakes produce before they could accurately describe the nature of earthquakes or their fundamental causes, as discussed in Lessons 1–5.

List the causes of seismic waves Describe the differences between P-waves and S-waves Explain how seismic waves can be used to investigate the Earth’s internal structure This lesson is suitable for ...

Explain how sound waves travel through different types of media Describe in basic terms how a loudspeaker works Use the terms longitudinal wave, compression and rarefaction Describe how our ears ...