Tag: physics

Questions Related to physics

The persistence of audible sound due to the successive reflections from the surrounding objects even after the source has stopped to produce that sound is called

physics study of sound reverberation applications of reflection of sound multiple reflection of sound and reverberation applications of ultrasound

  1. reflection

  2. echo

  3. reverberation

  4. rarefaction

Show answer
Correct Option: C
Explanation:

According to the definition of reverberation, it is the persistence of audible sound due to the successive reflections from the surrounding objects even after the source has stopped to produce that sound.

Reverberation time of a hall used for speeches should be very short. Why?

physics study of sound reverberation applications of reflection of sound multiple reflection of sound and reverberation applications of ultrasound

  1. Multiple echos will enhance the sound quality.

  2. Multiple echos will interfere with the original sound

  3. Both a and b

  4. None of the above

Show answer
Correct Option: B
Explanation:

Reverberation time of a hall used by speeches should be very small so that due to multiple reflection of sound, we will hear the same voice again and again distracting our concentration to hear important points of the speech. If we hear same sound many times it will irritate us.

Curved surfaces which are used in big hall to direct the sound waves towards the people sitting in a hall are known as:

physics study of sound reverberation applications of reflection of sound multiple reflection of sound and reverberation applications of ultrasound

  1. megaphone

  2. hydrophone

  3. bulb horn

  4. none of the above

Show answer
Correct Option: D
Explanation:

Sound boards are the curves surfaces (concave) which are used in a big hall to direct the sound waves towards the people sitting in a hall. The source of sound is placed at the focus of the sound board.

Mark the correct statement .
i) rock music also becomes less pleasing with excessive reverberation.
ii) excessive reverberation is desirable in case of orchestral and choral music.
iii) excessive reverberation makes the speech of a person indistinct.

physics study of sound reverberation applications of reflection of sound multiple reflection of sound and reverberation applications of ultrasound

  1. i, ii

  2. ii, iii

  3. i, iii

  4. all

Show answer
Correct Option: D
Explanation:

Reverberation is the phenomenon of persistence of sound after it has been stopped as a result of multiple reflections from surfaces such as furniture, people, air etc. within a closed surface. But the excessive reverberation is undesirable as the sound produced will continue to be heard repeatedly while the next sound being sent forth. This is unpleasant to hear and there is no clarity of sound.

So, all the statements are correct.

A device based on multiple reflection used as hearing aid.

physics study of sound reverberation applications of reflection of sound multiple reflection of sound and reverberation applications of ultrasound

  1. bulb horn

  2. ear trumpet

  3. megaphone

  4. all

Show answer
Correct Option: B
Explanation:

Ear trumpet or hearing aid is used by the persons who are hard of hearing. The sound waves received by the wide end of the trumpet are reflected into a much narrower area.

If the ceiling of a cineural is made flat, what will happen

physics study of sound reverberation applications of reflection of sound multiple reflection of sound and reverberation applications of ultrasound

  1. no sound will be audible at all.

  2. picture will vanish.

  3. sound will not reach properly to every person.

  4. picture will not be clear to everyone

Show answer
Correct Option: C
Explanation:

Ceiling in a cinema hall is made curve so that the sound of music, dialogue etc must reach evenly to all the audience.
So that the sound after reflection from curved surface reaches all corners of the hall evenly.

Identify the device which work on the reflection of light:

physics study of sound reverberation applications of reflection of sound multiple reflection of sound and reverberation applications of ultrasound

  1. megaphone

  2. stethoscope

  3. sound boards

  4. All

Show answer
Correct Option: C
Explanation:

Sound board is device which works on the reflection of light while others works on the reflection of sound.

Excessive reverberation in any auditorium/hall is not desirable because :

physics study of sound reverberation applications of reflection of sound multiple reflection of sound and reverberation applications of ultrasound

  1. sound becomes blurred

  2. sound become distorted

  3. sound remains same 

  4. both A and B

Show answer
Correct Option: D
Explanation:

Excessive reverberation in any auditorium or hall is not desirable because the sound becomes blurred and distorted. So the reverberation needs to be reduced.

Megaphones or loudhailers, horns, musical instruments such as trumpets and  shehnais, are all designed to ______.

physics study of sound reverberation applications of reflection of sound multiple reflection of sound and reverberation applications of ultrasound

  1. send sound in a particular direction without spreading it in all directions.

  2. send sound in a particular direction spreading it in all directions.

  3. collect sound from all directions spreading it in all directions.

  4. all of the above

Show answer
Correct Option: A
Explanation:

Megaphones or loudhailers, horns, musical instruments such as trumpets and shehnais, are all designed to send sound in a particular direction without spreading it in all direction.
In these instruments, a tube followed by a conical opening reflects sound successively to guide most of the sound waves from the source in the forward direction towards the audience.

Why the ceiling of concert halls, cinema halls made curved?

physics study of sound reverberation applications of reflection of sound multiple reflection of sound and reverberation applications of ultrasound

  1. To make the hall beautiful

  2. For proper light conditions

  3. So that the sound can reach all corners properly

  4. So that the picture or the stage can be visible to each and every person.

Show answer
Correct Option: C
Explanation:

In concert halls, cinema halls, conference halls, the ceiling are made curved, so that the sound after reflection from the curved surface reaches all corners of the hall evenly.