With reference to 'Body Waves', consider the following statements: 1. They are generated due to the release of energy at the focus. 2. They move only in a vertical direction towards the surface. 3. They interact with surface rocks to generate surface waves. Which of the statements given above is/are correct?

The correct option is 1 and 3 only. Explanation Earthquake waves are broadly classified into two categories: Body Waves and Surface Waves. Body waves are the primary waves generated during a seismic event and travel through the Earth's interior. - Statement 1 is Correct: Body waves are generated due to the release of energy at the focus (hypocenter). This energy release occurs when the lithospheric plates move or slip past one another, sending seismic waves through the Earth's body. - Statement 2 is Incorrect: Body waves do not travel only in a vertical direction. They travel in all directions from the focus through the body of the Earth. They radiate spherically outward from the source, similar to sound waves in air. - Statement 3 is Correct: As body waves travel through the Earth and reach the surface, they interact with the surface rocks. This interaction generates a new set of waves known as Surface Waves, which propagate along the Earth's surface. Key Takeaway: Body waves originate at the focus and travel omnidirectionally through the Earth's interior, whereas Surface waves are secondary effects generated when body waves interact with surface rocks.

NCERT Class 11 Geography — Chapter 2: Interior of the earth

mcqeasy

With reference to 'Body Waves', consider the following statements:

They are generated due to the release of energy at the focus.
They move only in a vertical direction towards the surface.
They interact with surface rocks to generate surface waves.

Which of the statements given above is/are correct?

Official previous-year question

Verified 1 Aug 2026.

Options

A1, 2 and 3
B1 and 3 only
C1 and 2 only
D2 only

Did you get this right?

Solution

The correct option is 1 and 3 only.

Explanation

Earthquake waves are broadly classified into two categories: Body Waves and Surface Waves. Body waves are the primary waves generated during a seismic event and travel through the Earth's interior.

Statement 1 is Correct: Body waves are generated due to the release of energy at the focus (hypocenter). This energy release occurs when the lithospheric plates move or slip past one another, sending seismic waves through the Earth's body.
Statement 2 is Incorrect: Body waves do not travel only in a vertical direction. They travel in all directions from the focus through the body of the Earth. They radiate spherically outward from the source, similar to sound waves in air.
Statement 3 is Correct: As body waves travel through the Earth and reach the surface, they interact with the surface rocks. This interaction generates a new set of waves known as Surface Waves, which propagate along the Earth's surface.

Key Takeaway: Body waves originate at the focus and travel omnidirectionally through the Earth's interior, whereas Surface waves are secondary effects generated when body waves interact with surface rocks.

Your note

More from Chapter 2: Interior of the earth

Which of the following statements is correct regarding the 'Shadow Zone' of P-waves?

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With reference to the 'Mantle', consider the following statements: 1. The lower mantle is in a liquid state. 2. It extends from Moho's discontinuity to a depth of 2,900 km. 3. It has a lower density than that of the crust. Which of the statements given above is/are correct?

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Consider the following statements regarding the 'Crust': 1. It is the innermost solid part of the earth. 2. It is brittle in nature. 3. Its thickness varies between oceanic and continental areas. Which of the statements given above is/are correct?

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With reference to the sources of information about the interior of the earth, consider the following statements: 1. Mining and drilling projects provide direct information about the earth's interior materials. 2. Meteors are considered a direct source of information because they originate from the earth's core. 3. Gravitation and magnetic fields are indirect sources of information. Which of the statements given above is/are correct?

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The magnitude of an earthquake, as measured by the Richter scale, indicates:

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The correct option is 1 and 3 only.

Explanation

Earthquake waves are broadly classified into two categories: Body Waves and Surface Waves. Body waves are the primary waves generated during a seismic event and travel through the Earth's interior.

Statement 1 is Correct: Body waves are generated due to the release of energy at the focus (hypocenter). This energy release occurs when the lithospheric plates move or slip past one another, sending seismic waves through the Earth's body.
Statement 2 is Incorrect: Body waves do not travel only in a vertical direction. They travel in all directions from the focus through the body of the Earth. They radiate spherically outward from the source, similar to sound waves in air.
Statement 3 is Correct: As body waves travel through the Earth and reach the surface, they interact with the surface rocks. This interaction generates a new set of waves known as Surface Waves, which propagate along the Earth's surface.