Reverberation

Q.

When a vibrating tuning fork is placed on a table, a loud sound is heard. This is due to

1. forced vibrations

2. free vibrations

3. beats

4. reflection

Q.

Multiple echoes are called reverberation.

1. True
2. False

Q. Why are the walls and roof of an auditorium covered with sound absorbent materials?

1. To maintain sound quality.
2. To reduce noise.
3. To reduce reverberation.
4. To increase pitch.

Q.

What happens if the reverberation time is too high?

1. The sound becomes infrasonic

2. The frequency becomes high

3. The sound becomes inaudible

4. Echoes are produced

Q. The roof and the walls of an auditorium are covered with sound-absorbing materials to avoid.

1. echo
2. multiple reflections
3. excessive frequency
4. loudness

Q. The reflection of sound can produce echoes.

1. \N
2. \N

Q.

What will happen when sound is focussed to a particular area?

1. Interference occurs

2. Echoes are produced

3. Sound becomes inaudible

4. Frequency of sound becomes high

Q.

The sound of explosion on the surface of a lake is heard by a boatman 100m away and by a diver 100 m below the point of explosion .Of the two persons who would hear the sound first? Give reason for your answer.

Q.

why are floors and ceilings of auditorium and theater covered by soundproof tiles?

Q.

What is reverberation?

1. Multiple reflections that result in persistence of sound

2. Inverse of direct sound

3. Inverse of an echo

4. Product of direct and reflected sound

Q. Pick the options where multiple reflection of sound can be observed.

1. Megaphone
2. Loudhailers
3. Cinema halls
4. Trumpets
5. Stethoscope
6. Outer space
7. Vacuum Chamber
8. Moon

Q.

The repeated reflections that result in the persistence of sound is called___.

Q.

Give two practical applications of reflection of sound waves.

Q. The echo will be heard if the original sound reflected by an obstacle reaches our ears after a minimum time of :

1. $10s$
2. $5s$
3. $1s$
4. $0.1s$

Q.

Why are the roof and the walls of an auditorium covered with sound-absorbing materials?

1. To reduce echo

2. To increase loudness

3. To control frequency

4. To reduce multiple reflections.

Q. causes undesirable effect inside an auditorium.

1. Reverberation
2. Loudness
3. Interference

Q. Assertion :Statement-1 : Echo is produced when sound is incident on hard and polished surface. Reason: Statement-2 : Sound energy can be totally reflected by objects with soft and loose texture.

1. Both Statements-1 and 2 are true and Statement-2 is the correct explanation of Statement-1.
2. Both Statements-1 and 2 are true but Statement-2 is not the correct explanation of Statement-1.
3. Statement-1 is true and Statement-2 is false.
4. Both Statements-1 and 2 are false.

Q.

Define reverberation.

Q. Which one of the following can make a big room less echoey?

1. ceiling
2. floor
3. carpet
4. wall

Q. The repeated reflection that results in the persistence of sound is called ___ .

1. noise
2. resonance
3. reverberation
4. echo

Q. Does sound follow the same laws of reflection as light? Give some real life examples of reflection of sound.
$\left[3\text{marks}\right]$

Q. Choose odd one out: