With reference to the movement of Earth's plates, consider the following statements: 1. When plates brush past one another, they cause disturbances in the earth's crust. 2. When a plate goes under another due to collision, it causes no disturbance in the crust. 3. These disturbances are confined to the core and do not affect the surface. Which of the statements given above are correct?

Correct Option The correct option is (a) 1 only. Explanation The the geological consequences of Plate Tectonics. The Earth's lithosphere is divided into several tectonic plates that move relative to each other. Their interactions at boundaries-convergent, divergent, and transform-are the primary sources of seismic activity (earthquakes) and volcanism. Statement-wise Analysis - Statement 1 is Correct: When tectonic plates brush past one another, it is known as a transform boundary (e.g., the San Andreas Fault). Friction often prevents the plates from sliding smoothly, causing stress to build up. When this stress is released, it causes sudden movements in the Earth's crust, resulting in earthquakes (disturbances). - Statement 2 is Incorrect: When a plate goes under another due to collision, a process called subduction occurs (convergent boundary). This process causes intense friction and stress accumulation, leading to some of the most powerful earthquakes and volcanic activity. It causes significant disturbance in the crust, contrary to the statement. - Statement 3 is Incorrect: These disturbances (earthquakes) originate in the lithosphere (the crust and the uppermost solid mantle). They are not confined to the core. The seismic waves generated by the rupture travel through the Earth's layers and cause tremors on the surface. Key Takeaway Earthquakes are tremors caused by the sudden release of energy in the Earth's crust resulting from the movement of tectonic plates. These disturbances occur at all plate boundaries (transform, convergent, and divergent) and directly affect the surface.

With reference to the movement of Earth's… - NCERT Class 8 Science MCQ

NCERT Class 8 Science — Chapter 3: Some natural phenomena

mcqmedium

With reference to the movement of Earth's plates, consider the following statements:

When plates brush past one another, they cause disturbances in the earth's crust.
When a plate goes under another due to collision, it causes no disturbance in the crust.
These disturbances are confined to the core and do not affect the surface.

Which of the statements given above are correct?

NCERT textbook question

From NCERT Science - class 8 · Page 9

Options

A1 only
B2 only
C1 and 3 only
D1, 2 and 3

Did you get this right?

Solution

Correct Option

The correct option is (a) 1 only.

Explanation

The the geological consequences of Plate Tectonics. The Earth's lithosphere is divided into several tectonic plates that move relative to each other. Their interactions at boundaries-convergent, divergent, and transform-are the primary sources of seismic activity (earthquakes) and volcanism.

Statement-wise Analysis

Statement 1 is Correct: When tectonic plates brush past one another, it is known as a transform boundary (e.g., the San Andreas Fault). Friction often prevents the plates from sliding smoothly, causing stress to build up. When this stress is released, it causes sudden movements in the Earth's crust, resulting in earthquakes (disturbances).
Statement 2 is Incorrect: When a plate goes under another due to collision, a process called subduction occurs (convergent boundary). This process causes intense friction and stress accumulation, leading to some of the most powerful earthquakes and volcanic activity. It causes significant disturbance in the crust, contrary to the statement.
Statement 3 is Incorrect: These disturbances (earthquakes) originate in the lithosphere (the crust and the uppermost solid mantle). They are not confined to the core. The seismic waves generated by the rupture travel through the Earth's layers and cause tremors on the surface.

Key Takeaway

Earthquakes are tremors caused by the sudden release of energy in the Earth's crust resulting from the movement of tectonic plates. These disturbances occur at all plate boundaries (transform, convergent, and divergent) and directly affect the surface.

Your note

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