Question
Why does a ray falling normally on a plane mirror, retrace its path?
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Answer
The ray traces its path when it falls normally on a plane mirror because the angle of incidence is equal to the angle of reflection.
Explanation: According to the 'law of reflection' the angle of 'incidence' is always equals to the "angle of reflection". If a ray falls normally it means it is falling on the 'plane mirror' at right angle. So the 'angle of incidence' is 90 degrees and so is the 'angle of reflection.
Explanation: According to the 'law of reflection' the angle of 'incidence' is always equals to the "angle of reflection". If a ray falls normally it means it is falling on the 'plane mirror' at right angle. So the 'angle of incidence' is 90 degrees and so is the 'angle of reflection.
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