Final answer:
A ray path is the route taken by seismic waves from the earthquake source to the seismometer. P-waves arrive before S-waves, and the arrival times can provide warning for impending seismic activity. Transverse waves are characterized by particles moving perpendicular to the wave direction.
Step-by-step explanation:
The ray drawn for a wave that travels by the most direct path from a seismic source to a seismometer is known as the ray path of the seismic waves. The ray path is critical in determining the distance to the epicenter of an earthquake by comparing the arrival times of P-waves (Primary waves) and S-waves (Secondary waves), which have different propagation speeds through the Earth.
1. When the particles of a medium move perpendicular to the direction of the wave motion, the wave is called a transverse wave. An example of this motion can be seen in water waves where the disturbance of the surface propagates parallel to the surface, while the medium (water) moves up and down.
a. P-waves, being faster, typically reach seismograph stations before S-waves. The difference in arrival times can be used to calculate how much warning a location may have before the onset of more serious shaking caused by S-waves.