# What are P, S, and L waves?

Jul 20, 2016

P, S and L waves refer to Primary, Secondary and Longitudinal waves. L is also the first letter in Love waves. See explanation.

#### Explanation:

Waves are propagated through a medium that is a solid or a fluid (

liquid or gas ). So, there is velocity in this propagation.

If the propagation is like or unlike, in the direction of the velocity, the

waves are called longitudinal. Otherwise, they are called transverse

waves..

Primary waves are bundle of longitudinal waves that travel

through both solid and fluid mediums.

Secondary waves are bundle of transverse waves that cannot

easily travel in a solid medium. The propagation depends on the

resistance (shear force ) offered by the medium. Naturally, the

resistance is more from solids. Of course, this resistance indeed

affects the propagation of primary waves.

Waves involve movement of ground, perpendicular to the

direction of the velocity of propagation. When the amplitude of

the motion is parallel to the surface, the wave is called a Love wave.

Reference:

$w i k i$ seismic waves

.