To hear an echo clearly, the reflected sound must reach the listener at least 0.1 seconds after the original sound. This time difference allows the human ear to distinguish the two sounds.
The sound travels to the reflecting surface and back to the listener. Therefore, the total distance covered by the sound is twice the distance to the surface.
Therefore, the reflecting surface should be at least 17 m from the listener to hear the echo clearly.
In a PA system, a _____ is used to adjust the amplitude of different frequencies to achieve the desired quality of sound output.
We hear an echo due to
An infrasound microphone enables the remote detection of aircraft wake vortices, clear air turbulence, tornadoes, and seismic events at frequencies below: