Question

Consider the following statements about seismic waves:

1. They help in understanding the Earth's internal layering.

2. They are considered a direct source of information about the Earth’s interior.

• A. 1 only
• B. 2 only
• C. Both 1 and 2
• D. Neither 1 nor 2

Answer 1

Answer:

A. 1 only

• Correct Answer: Option A) 1 only

• Seismic waves are vibrations that travel through the Earth's layers when energy is suddenly released, such as during earthquakes. Let's analyze each statement:

• Statement 1: They help in understanding the Earth's internal layering- True

• Seismic waves are crucial for understanding Earth's internal structure. When these waves travel through different layers of the Earth (crust, mantle, outer core, inner core), they behave differently:

• P-waves (primary waves) can travel through both solids and liquids

• S-waves (secondary waves) can only travel through solids

• The speed and direction of these waves change when they encounter boundaries between different layers

• By studying how seismic waves are refracted, reflected, and absorbed, scientists can map the Earth's internal layers and determine their properties

• Statement 2: They are considered a direct source of information about the Earth's interior- false

• Seismic waves provide indirect information about Earth's interior, not direct information. We cannot directly observe or sample the Earth's deep interior layers. Instead, we interpret the behavior of seismic waves as they travel through these layers to infer the properties and structure of the Earth's interior. This is similar to how doctors use X-rays to see inside the human body - the information is obtained indirectly through wave behavior.