Echo is not heard in a room of 10 m x 10 in x 10 m dimension due to (speed of sound in air = 300 m/s)a)reflectionb)absorptionc)persistenced)humidityCorrect answer is option 'C'. Can you explain this answer?

Question

Answer

If you have persistence, you continue to do something even though it is difficult or others are against it.

( As the sensation of sound persists in our brain for about 0.1 s, to hear a distinct echo the time interval between the original sound and the reflected one must be at least 0.1 s. If we take the speed of the sound to be 300 m/s at a given temperature, in air, sound must go to the obstacle and reach back the ear of the listener on reflection after 0.1s. )

Answer

an Echo cannot be heard because of PERSISTENCE of hearing which means that it is just the sensation of hearing, it should be in reach of 0.1 sec then only echo could be heard

Answer

No its a due to reflectionspeed is to fastthat we could not hear echo

Answer

Explanation:

1. Reflection:
When sound waves hit a surface, they can bounce back off the surface and return to the source of the sound. This is called reflection. However, in the given scenario, echo is not heard in the room, which means that the sound waves are not reflecting off the walls and returning to the listener.

2. Absorption:
When sound waves hit a surface, they can also be absorbed by the surface. This means that the energy of the sound waves is converted into heat energy by the surface material. In the given scenario, it is unlikely that the sound waves are being completely absorbed by the walls of the room, as the walls are typically made of materials that reflect sound to some extent.

3. Persistence:
Persistence refers to the duration for which a sound wave lingers in a space. In the given scenario, the absence of echo suggests that the sound waves are not persisting in the room for a noticeable amount of time. This could be due to the presence of sound-absorbing materials or the shape of the room, which might cause the sound waves to disperse or dissipate quickly.

4. Humidity:
Humidity refers to the amount of moisture present in the air. It has no direct effect on the reflection or absorption of sound waves. While high humidity can affect the speed of sound, it is not a significant factor in the absence of echo in the given scenario.

Therefore, the correct answer is option 'C' - persistence. The sound waves in the room are not persisting for a noticeable amount of time, resulting in the absence of echo.

Answer

It is due to reflection

Answer

Answer is C

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