​Which of the following statements are true about seismic waves?

• A. The velocity of P-wave depends upon density and distortion to compression of rock traversed.
• B. P-wave travels faster than S-wave.
• C. L-wave follows a zig-zag path and arrives later than P and S-waves.
• D. The velocity of S-wave depends upon density and resistance of rock traversed.

Correct option is D

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1. (B) P-wave travels faster than S-wave.
   Correct – P-waves are primary (compressional) waves and are the fastest among seismic waves, moving through both solids and liquids.

2. (C) L-wave follows a zig-zag path and arrives later than P and S-waves.
   Correct  – Love waves (L-waves) travel along the surface and arrive after body waves (P and S). While "zig-zag" is not the most accurate term, it is somewhat acceptable as surface waves have complex motion.

Information Booster:

• P-waves are the fastest seismic waves and travel through both solids and liquids.
• S-waves are slower than P-waves and only travel through solids, making them useful in studying Earth's interior.
• L-waves (Love waves) are surface waves and cause significant damage in earthquakes due to their lateral motion.
• Rayleigh waves, another type of surface wave, travel with an elliptical motion, unlike L-waves.
• Seismic wave velocities depend on the material properties (density, elasticity) rather than just resistance.
• Seismologists use P and S-waves to determine earthquake epicenters and Earth's internal structure.

Additional Knowledge:

The velocity of P-wave depends upon density and distortion to compression of rock traversed: 

• Primary waves (P-waves) are compressional waves. They cause particles to move parallel to the wave’s direction.
• Travel through solids, liquids, and gases, making them crucial for detecting earthquakes at distant locations.
• Their speed is higher in denser, elastic materials due to better transmission of compressional forces.

Seismic wave velocity and Earth's structure:

• Seismic waves travel at different speeds depending on rock density and elasticity.
• Seismologists analyze P and S-wave travel times to study Earth's internal layers (crust, mantle, core).
• Shadow zones exist where P and S-waves do not reach due to refraction and absorption.