Solution:

Multiple reflection of light is the reflection of light back and forth several times between reflecting surfaces. If a reflected light ray is reflected again on being incident on another surface, it is termed multiple reflections. Multiple reflections are used in periscopes.





In physics, interference is a phenomenon in which two waves superpose to form a resultant wave of greater, lower, or the same amplitude. Constructive and destructive interference result from the interaction of waves that are correlated or coherent with each other, either because they come from the same source or because they have the same or nearly the same frequency. Interference effects can be observed with all types of waves, for example, light, radio, acoustic, surface water waves, gravity waves, or matter waves. The resulting images or graphs are called interferograms.