Question

The persistence of sound in a hall is called
A.) reverberation
B.) resonance
C.) acoustics
D.) articulation

Answer 1

Hint: The prolongation of sound is related to something which means having continuous effect. These effects can be due to multiple reflections.

Complete step by step answer:
To answer the given question, first of all we should know the meaning of the terms mentioned in the option. Without knowing the exact meaning of all the options mentioned in the question, there is a high chance that we might make a mistake in choosing the correct answer, so let us first discuss the meaning of these words.

Definitions:

a.) Reverberation - Reverberation is the phenomenon of persistence of sound even after it has been stopped. This occurs because of the reflections from surfaces inside a closed surface. In other words, we can say that reverberation is the overlapping of sounds caused by multiple reflections on the surfaces.

b.) Resonance - Resonance is the phenomenon by which an external force forces a system which lies around it to oscillate with a greater amplitude in comparison with the original amplitude of the system, at a particular frequency of oscillation.

Important - Resonance occurs when the frequency of a periodically applied force is equal or close to a natural frequency of the system on which it acts.

c.) Acoustics - Acoustics is a branch of Physics which deals with the study of mechanical waves in all states of matter. In this case, we need to know what mechanical wave means. So, a mechanical wave is the wave which transfers energy through a medium.

d.) Articulation - Articulation refers to the production of clear and distinct sounds, like in a speech.

So, after going through the definitions of the given options, we can see that although all the words are related to sound, but every particular word has a different meaning, and the appropriate answer to the given question should be reverberation, as it refers to the prolongation of sound, even after the source of sound has been stopped from producing more sounds. We could of thought of resonance, but we must keep a very important thing in mind, that,resonance of a system is always related to the highest amplitude, but is the question, we have been asked not about the amplitude, but about the persistence of sound in a hall, during which the amplitude keeps on decreasing and therefore the correct answer should be reverberation.

Therefore, the answer is, option A- reverberation.

Additional Information:
A reverberation (reverb), is created when a sound or signal is reflected causing multiple reflections to build up and then decay gradually as the sound is absorbed by the surfaces of objects in the space.

Note: Reverberation means the persistence of sound for a long period of time, with gradually decreasing amplitude, but in resonance we basically deal with the point with highest amplitude.