EARTH SCIENCE
EARTHQUAKES
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
P waves
|
|
S waves
|
|
surface waves
|
|
None of the above
|
Detailed explanation-1: -P waves travel fastest and are the first to arrive from the earthquake. In S or shear waves, rock oscillates perpendicular to the direction of wave propagation. In rock, S waves generally travel about 60% the speed of P waves, and the S wave always arrives after the P wave.
Detailed explanation-2: -Because P waves are the fastest seismic waves, they will usually be the first ones that your seismograph records. The next set of seismic waves on your seismogram will be the S waves.
Detailed explanation-3: -P waves can travel through liquid and solids and gases, while S waves only travel through solids. Scientists use this information to help them determine the structure of Earth. For example, if an earthquake occurs on one side of Earth, seismometers around the globe can measure the resulting S and P waves.
Detailed explanation-4: -Earthquakes shake the ground because fault rupture releases vibrations that radiate in the form of seismic energy. These earthquake waves, also called body waves, come in two distinct forms: Primary or āPā waves and Secondary or āSā waves.
Detailed explanation-5: -P waves, or Primary waves, are the first waves to arrive at a seismograph. P waves are the fastest seismic waves and can move through solid, liquid, or gas. They leave behind a trail of compressions and rarefactions on the medium they move through. P waves are also called pressure waves for this reason.