Manjula is observing her image in a plane mirror. The distance between herself…

Concept: In a plane mirror, the image formed is virtual and located exactly as far behind the mirror as the object stands in front of it. So the image distance from the mirror always equals the object distance from the mirror, and the total separation between the object and its image equals the sum of these two equal distances (i.e., twice the object's distance from the mirror).

Application:

1. Initially, the distance between Manjula and the mirror is 5 m.

2. She moves 1 m towards the mirror, so her new distance from the mirror = 5 m − 1 m = 4 m.

3. By the plane-mirror property, her image now forms 4 m behind the mirror, since the image distance always equals the object distance.

4. The total separation between Manjula and her image = her distance in front of the mirror + the image's distance behind the mirror = 4 m + 4 m = 8 m.

Cross-check: Using the direct relation, separation = 2 × (new distance from the mirror) = 2 × 4 m = 8 m, which matches the value obtained above.

Hence, the distance between Manjula and her image now is 8 m.