Question

Why are 2 plane mirrors placed at an angle of 45 degree in a periscope ?

Answer 1

because see,
first in a periscope we need to deviate the light or simply saying we need to change the direction of the light.so placing the mirror at exactly 45 degree will deviate the light perpendicularly and thus the second mirror also placed at 45 degree will deviate the light perpendicularly ,and hence the light reaches our eyes.
and we are able to see the picture.


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