Question

two applications of echo?

Answer 1

Echo is the multiple repetition of a sound produced after bouncing from any hard and rigid surface.
Applications of Echo are---
1) In the megaphones. One end of the megaphone is narrow while other side is wide.It is used in gatherings to make loud announcements to the public.
2) Another application is stethoscope . The vibrations that are produced in the tube of the stethoscope helps the doctors to listen to the sound from heart or lungs.

Answer 2

Echo is a sound which is bounced back or we say reflection of sound,echo is produced when the sound is touched to a hard but smooth surface.

1)It only reflects at a distance of 27 m.
2)It is used in reducing muscular pain.

Hope it helped you................