The question asks to identify the instrument used for recording earthquake waves. This requires knowledge of common scientific instruments and their functions.
Correct Option: A) Seismograph is the correct answer. A seismograph is an instrument that detects and records ground motion caused by seismic waves, which are generated during an earthquake. The record produced by a seismograph is called a seismogram.
This question tests knowledge about different types of earthquake waves and their propagation speeds. Understanding the characteristics of P-waves, S-waves, and surface waves is crucial to determine which one arrives first at the Earth's surface.
Correct Option: B) P-waves (Primary waves) are the fastest seismic waves and thus arrive first at the Earth's surface.
The question asks to identify the type of earthquake waves that can travel exclusively through solid materials. This requires understanding the fundamental properties of different seismic waves, specifically P-waves and S-waves, and their propagation through various states of matter.
Based on these properties, S-waves are the only type of earthquake body waves that can travel exclusively through solid materials.
B) S-waves (Secondary waves) are shear waves that require a medium with shear strength to propagate. Since only solids possess significant shear strength, S-waves can travel only through solid materials and are blocked by liquids and gases.
The question asks to identify the type of wave that P-waves (Primary waves) are similar to. This requires understanding the fundamental characteristics of P-waves and comparing them to the given options.
C) Sound waves — P-waves are longitudinal (compressional) waves, meaning they cause particles in the medium to vibrate parallel to the direction of wave propagation, just like sound waves. Both require a medium to travel.
The question asks about the direction of vibration of S-waves (secondary or shear waves). To answer this, we need to understand the fundamental characteristics of S-waves, particularly how their particle motion relates to their direction of propagation.
D) Perpendicular to the direction of propagation in the vertical plane. This option correctly describes the transverse nature of S-waves. The particles of the medium oscillate at right angles (perpendicular) to the direction the wave is traveling. This perpendicular vibration can occur in any plane perpendicular to the propagation direction, including the vertical plane.
To determine which earthquake waves are most destructive, we need to understand the different types of seismic waves and their characteristics, particularly how they interact with the Earth's surface and structures.
Correct Option: A) Surface waves are considered the most destructive earthquake waves because they travel along the Earth's surface, have larger amplitudes, and cause complex ground motion that is highly damaging to structures.