Tag: acoustics

An echo is the repetition of sound that results as a reflection from a surface. An echo of the sound produced can be heard only if it reaches our ear after 1 / 10th of a second. This is due to the persistence of sound.

we can hear echoes anywhere, where the distance between the source and the point of reflection is sufficient enough.

The time gap between the two sounds-direct and echo depends upon the medium through which the sound travels. These two sounds can be heard distinctly provided the Distance between the observer and the reflecting surface is large enough to allow the reflected sound to reach him without interfering with the direct sound.

The time gap between the two sounds-direct and echo depends upon the medium through which the sound travels. These two sounds can be heard distinctly provided the Distance between the observer and the reflecting surface is large enough to allow the reflected sound to reach him without interfering with the direct sound.

In rooms having walls less than 17.2 m away from each other, no echo can be heard.

For the production of an echo, the reflecting surface or the obstacle should be rigid such as building, hill, cliff.
Echo can be produced if the size of the obstacle reflecting the sound is quite large.

The minimum distance in air between the observer and the obstacle for an echo to be heard clearly at temperatures higher than $25^o$C is more than 17.2 m.
The speed of sound increases with rise in temperature.

For the production of an echo, the reflecting surface or the obstacle should be rigid such as building, hill, cliff.

The minimum distance in air between the observer and the obstacle for an echo to be heard clearly is nearly 17.2 m. This condition is followed here but for the production of an echo, the obstacle should be rigid.

$1.$ Echo is simply the reflection of sound that arrives at the listener with a delay after the direct sound.