Chapter 4 Test Flashcards
a push or pull exerted on an object
Force
a measure of the amount of matter an object contains and its resistance to movement
Mass
the amount of space that matter occupies
volume
the shaking and trembling that results from movement of rock beneath Earth’s surface
earthquake
the area beneath Earth’s surface where rock that was under stress that begins to break or move
focus
seismic waves that compress and expand the ground like an accordion
p waves
the point on the surface directly above the focus
epicenter
seismic waves that can vibrate from side to side and up and down
s waves
move more slowly than p or s waves, but can produce severe ground movements
surface waves
an instrument that records and measure an earthquakes seismic waves
seismograph
a single number that geologists assign to an earthquake based on the earthquake’s size
magnitude
rates the amount of shaking from an earthquake
Modified mercalli scale
rates the magnitude of small earthquakes based on the size of the earthquake’s waves as recorded by seismographs
richter scale
rates the total energy and earthquake releases
moment magnitude scale
a force that acts on rock to change its shape or volume
stress
