What is the angle of incidence of a ray of light if the reflected ray is at an angle of 90° to the incident ray?

the angle of incidence= angle of reflection.

According to the question, given i+r= 90 degree


i=r


hence i+i=90 degree


2i=90 degree.


I=45 degree.
Therefore, the angle of incidence is 45 degree.


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