Sita, 1·5 m high, stands before a plane mirror fixed on a wall to view her full image. What should be the minimum height of the plane mirror so that Sita can view her image fully ?
0·50 m
0·35 m
0·75 m
0·25 m
Answer is Right!
Answer is Wrong!
This question was previously asked in
UPSC NDA-2 – 2023
For a person of height H standing in front of a plane mirror, the minimum height of the mirror needed to see the entire image is H/2. This is because of the law of reflection; light rays from the top of the head and the bottom of the feet reflect off the mirror into the observer’s eyes. The reflection point for the feet is halfway between the feet and the eyes’ height, and similarly for the top of the head.