GCSE Physics - Seismic Waves #75

The video explains seismic waves, focusing on P waves and S waves. P waves are longitudinal and travel through solids and liquids, while S waves are transverse and only travel through solids. Seismologists use these waves to study Earth's internal structure. Waves can be reflected, absorbed, or refracted at boundaries, with refraction occurring due to changes in density. P waves can travel through the liquid outer core, but S waves cannot, providing clues about Earth's layers. The video highlights how wave detection helps scientists understand Earth's composition.

Which type of seismic wave can travel through both solids and liquids?

• P waves

• S waves

• Rayleigh waves

• Surface waves

What device do scientists use to detect seismic waves?

• Thermometer

• Barometer

• Telescope

• Seismometer

What happens to seismic waves when they reach a boundary between two different mediums?

• They disappear

• They speed up

• They can be reflected, absorbed, or transmitted

• They always stop

Why can't S waves travel through the Earth's outer core?

• Because it is a liquid

• Because it is too dense

• Because it is too hot

• Because it is too far

What was one of the main clues that led scientists to discover the liquid outer core?

• The absence of S waves in certain regions

• The speed of P waves

• The temperature of the core

• The reflection of surface waves