A "quick" slow motion clip illustrates how a seismograph measures the vertical motion of S and P waves. [0:13]

A series of videos describing wave characteristics.

A video with definitions and examples of reflection and refraction. An optional post quiz also included.

As seismic waves from earthquakes pass through the planet, their patterns can reveal hidden dynamics-hotspots, deep-diving rock, melting mantle-in Earth's interior. An array of seismometers that's being installed across the United States...

Seismic waves travel through the earth to a single seismic station. Scale and movement of the seismic station are greatly exaggerated to depict the relative motion recorded by the seismogram as P, S, and surface waves arrive. [0:50]

Video lecture explores S-waves and P-waves. [8:38]

Explains how any type of wave can be refracted, and how this applies to seismic waves and to our understanding of the Earth's structure. [9:21]

This video segment, adapted from ZOOM, explores how sound waves travel differently through solids than through air, in this case, a metal clothes hanger. [1:14]

Introduction to transverse and longitudinal waves.

Discover waves and optics by learning about refraction in water. [4:25]

See a cow and a tree in this narrated cartoon for fun and to emphasize that seismic waves traveling away from an earthquake occur everywhere, not just at seismic stations. [1:31]

Video lecture describing speeds and paths of different seismic waves within Earth from an earthquake to a distant seismic station. P & S waves travel through the Earth; Surface waves travel around the perimeter of the Earth. [1:44]

Video lecture on wave motions and speeds of three fundamental kinds of seismic waves: Primary (P = pressure) waves; Secondary (S = shear); and Surface waves. [3:10]

See how travel-time curves are created. [2:52]

See what seismograms look like at increasing distances from the epicenter. [0:21]

See how surface waves and P and S-Waves affect Earth's surface. [0:36]

See how a seismograph can help determine the strength of a hurricane. [5:19]

A middle school science teacher demonstrates how a slinky is a good analogy for P & S seismic waves. [5:13]

This demonstration shows that seismic waves propagate in all directions in the Earth from the source (not just in the direction of a single slinky). [5:13]

This demonstration explores two of the four (P and S waves) main ways energy propagates from the hypocenter of an earthquake. [8:27]

A cross section of the shallow crust in the Basin & Range. The earthquake produces seismic waves that bump an array of seismic stations. [0:30]

How fast does sound travel through the rocks? And how does seismic velocity vary through different depths? See how scientists measure individual pieces of seafloor samples to get a better understanding of how the cores are related to...

In this video, review over the topics of Hooke's law, simple harmonic motion, waves and wave interference, Doppler effect, standing waves, and beat frequency. Practice for your AP Physics 1 test. [19:54]

How fast does sound actually travel? [3:44]