Which of the following seismic waves cannot travel through liquids?
- A.P waves
- B.S waves
- C.Love waves
- D.Rayleigh waves
Correct answer
Explanation
The correct answer is B, S waves. Secondary or S waves are transverse, so the particles of the medium move at right angles to the direction of travel. A transverse wave needs a medium that resists a change of shape, and a liquid does not, so S waves stop at the liquid outer core and are not recorded beyond about 103 degrees from the epicentre.
Option A, P waves, are longitudinal waves of compression and rarefaction and pass through solids, liquids and gases alike, which is why they are always the first to be recorded. Options C and D, Love and Rayleigh waves, are surface waves; they travel only along the crust and are the slowest and the most destructive, but the question is about passage through liquids inside the earth, which they never attempt. The absence of S waves in the shadow region is the standard proof that the outer core of the earth is in a liquid state.
Read the full article: Earthquakes and Volcanoes: Waves, Belts and Types
Practice Questions
View allThe point inside the earth where an earthquake originates is known as the
- A.Epicentre
- B.Fault line
- C.Focus
- D.Shadow zone
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The focus, also called the hypocentre, is the point below the surface at which the strained rock ruptures and releases its stored elastic energy as seismic waves.
Read the full explanation →The Richter scale is used to measure which of the following?
- A.Intensity of damage caused by an earthquake
- B.Magnitude of energy released by an earthquake
- C.Depth of the focus of an earthquake
- D.Height of tsunami waves
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The Richter scale, devised by Charles F. Richter in 1935, expresses the energy released at the source of the shock.
Read the full explanation →Barren Island, the only active volcano in India, is located in which of the following?
- A.Lakshadweep
- B.Gulf of Kutch
- C.Andaman and Nicobar Islands
- D.Sundarbans delta
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Barren Island lies in the Andaman Sea, to the east of the main Andaman group, and is the only active volcano in India and in South Asia.
Read the full explanation →The instrument used to record the waves produced by an earthquake is called a
- A.Seismograph
- B.Barograph
- C.Hygrometer
- D.Altimeter
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A seismograph carries a mass that stays nearly still while the ground and the frame move under it, and the relative motion is traced as a wavy line.
Read the full explanation →Mount Vesuvius, the volcano whose eruption buried the city of Pompeii, is located in which country?
- A.Greece
- B.Italy
- C.Turkey
- D.Spain
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Mount Vesuvius stands near the Bay of Naples in southern Italy and its eruption in 79 CE buried the Roman towns of Pompeii and Herculaneum under ash, preserving them so well that they became an archaeological record of Roman daily life.
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