Answer:
Rayleigh waves, also known as ground roll or Rayleigh waves, are a type of surface wave that travels along the surface of the Earth. They are one of the two main types of surface waves produced by seismic activity, with the other being Love waves. Rayleigh waves are named after the British scientist Lord Rayleigh, who mathematically predicted their existence in the 19th century.
Explanation: Motion: Rayleigh waves have a rolling motion, similar to ocean waves. The particles of the medium (usually the Earth's crust) move in an elliptical, retrograde (opposite to the direction of wave propagation) path. This rolling motion is what makes Rayleigh waves particularly destructive during earthquakes, as it can cause the ground to move in a circular pattern.
Speed: Rayleigh waves travel slower than body waves (such as P-waves and S-waves) but faster than Love waves. The speed of Rayleigh waves depends on the properties of the medium through which they travel.
Amplitude: Rayleigh waves have larger amplitudes than body waves, which means they can cause more significant ground motion and damage during seismic events.
Dispersion: Rayleigh waves are dispersive, meaning that their velocity depends on their frequency. Higher frequency Rayleigh waves travel slightly faster than lower frequency ones.
Propagation: Rayleigh waves can travel across all types of surfaces, including land, water, and ice. They are typically generated by the interaction of body waves with the Earth's surface.