Question

define multiple reflection and multiple echoes

Answer 1

Multiple reflection : Multiple reflection of light is the reflection of light back and forth several times between reflecting surfaces. Kaleidoscope is an optical instrument which uses multiple reflections.
Multiple echoes : Multiple echoes are arised due to the multiple reflection of sound.  Reflection is the bouncing back of sound when it strikes a hard surface.
 

Answer 2

when light reflect off a mirror,one image apper two mirror placed exactly face to face give the apprence of an infinite numbers of images along a stright line the multiple image seen .. this is called as multiple reflection


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