Reverberation is a phenomenon associated with a
- A.multiple refraction of sound.
- B.multiple reflection of sound.
- C.single refraction of sound.
- D.single reflection of sound.
Correct answer
Explanation
The correct answer is B, multiple reflection of sound. Reverberation is the persistence of sound in a hall after the source has stopped, caused by repeated reflections from the walls, ceiling and floor.
In a large closed space, sound bounces many times between hard surfaces, and these reflections reach the listener one after another so quickly that they merge into a lingering sound. Too much reverberation makes speech and music blurred, so auditoriums and cinema halls use sound-absorbing materials such as fibre boards, rough plaster, heavy curtains and padded seats, and ceilings are often curved to spread sound evenly. An echo is different: it is a single distinct reflection heard separately, which needs the reflecting surface to be at least about 17 metres away so that the reflected sound arrives 0.1 second or more after the original.
A is wrong because refraction is the bending of sound on passing between media, not its bouncing back. C is wrong for the same reason. D is wrong because a single reflection heard distinctly is an echo, not reverberation.
Exam tip: One reflection heard separately = echo (17 m or more); many reflections merging = reverberation.
Practice Questions
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- B.Galvanometer
- C.Viscometer
- D.Diffractometer
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- D.Charges can be created and destroyed in an isolated system
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Read the full explanation →Which of the following organelles have their own DNA and ribosomes?
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- B.Mitochondria and Chloroplast
- C.Endoplasmic reticulum and cytoskeleton
- D.Cell wall and nucleolus
Show answer
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Read the full explanation →Which one of the following statements is NOT correct ?
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- B.Mostly enzymes are proteins
- C.All fats are energy rich compounds
- D.Glucose is a common carbohydrate
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Read the full explanation →Which one of the following types of radiations has the smallest wavelength?
- A.Microwaves
- B.Infra-red
- C.Visible light
- D.X-rays
Show answer
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