Document page
igcse physics notesprinted 93 · PDF 93
124 pagesrevision 46936
printed 93 · PDF 93
Page image rendered from the stored file at 110 dpi; it sharpens as you zoom. Outlines are placed from each region’s stored position on the page (612 × 792 pt).
readable
Source of this text: embedded text layer. The better of the embedded text and OCR is kept.
93
Seismic Waves:
Earthquakes are caused by sudden rock movement underground. The
vibrations send “Seismic Waves” (Shock Waves) through the Earth.
These waves get weaker as they travel through the ground.
Types of Seismic Waves:
P-Waves (Primary waves): These are longitudinal waves. They are the
fastest and arrive first. They travel through solids and liquids deep in the
earth at a speed of several Kilometers per second. Their speed is highest
through Solids.
S-Waves (Secondary waves): They are transverse waves. They arrive after
the primary waves because they are slower. They can pass through solids
deep in the Earth, but not through liquids such as melted rocks.