A lady is standing in front of a plane mirror at a distance of 1 m from it. She walks 60 cm towards the mirror. The distance of her image now from herself (ignoring the thickness of the mirror) is
40 cm
60 cm
80 cm
120 cm
Answer is Wrong!
Answer is Right!
This question was previously asked in
UPSC NDA-1 – 2016
Initially, the lady is at a distance of 1 m (100 cm) from the mirror. Her image is formed 100 cm behind the mirror. The distance between the lady and her image is 100 cm (lady to mirror) + 100 cm (mirror to image) = 200 cm.
The lady walks 60 cm towards the mirror. Her new distance from the mirror is 100 cm – 60 cm = 40 cm.
Her new image is formed 40 cm behind the mirror.
The new distance between the lady and her image is her distance from the mirror + her image’s distance from the mirror = 40 cm + 40 cm = 80 cm.
– Image is behind the mirror.
– Distance between object and image is (object distance) + (image distance) = 2 * (object distance).