Question

Which one of the following scismic Waves involves compression and rarefaction (but not rotation) of the material that it passes through?

• A. P-waves
• B. S-waves
• C. Rayleigh waves
• D. Love Waves

Answer 1

The Correct Option is A

To solve this question, it's essential to understand the types of seismic waves and their characteristics. Here are the key details about each type:

• P-waves (Primary waves): These are the fastest seismic waves and travel through solids, liquids, and gases. They cause the material they pass through to compress and rarefy in the direction of propagation. This compression and rarefaction is akin to sound waves in the air. P-waves do not involve any rotational motion of particles.
• S-waves (Secondary waves): They are slower than P-waves and can only travel through solids. These waves cause particles to move perpendicular to the direction of wave propagation, producing a shearing motion. S-waves involve rotation as they cause the material to twist.
• Rayleigh waves: These are surface waves that travel along the ground's surface. They cause an elliptical motion of particles, resulting in both horizontal and vertical movement, but they are not characterized by pure compression and rarefaction.
• Love waves: Another type of surface wave, these move the ground side-to-side. They involve a horizontal shearing motion and do not incorporate compressional or rarefaction movements.

Given this information, the correct answer to the question is P-waves. They involve compression and rarefaction of the material as they pass through, without causing rotation.

By understanding the characteristics of these seismic waves, it's clear that the only type involving compression and rarefaction, without rotation, is P-waves.