Echo of sound is due to _____________ of sound.
When a sound is reflected from a distant object, an echo is produced. Let the distance between the reflecting surface and the source of sound production remains the same. Do you hear echo sound on a hotter day?
Fill in the following blanks with suitable words :
(a) An echo is simply a ___ sound .
(b) Pitch of sound depends on ___ .
(c) Loudness of sound depends on ___ .
(d) Quality of sound depends on ___ .
(e) Echoes are caused by the ___ of sound .