Question

When do u take image distance positive or negative?

When do u take object distance negative or positive?

Plzz explain it in detail

Answer 1

1. Distances measured in the direction of incident light are always taken as positive whereas the distance measured in opposition to the direction of incident light is taken as negative.
2. The upward distances perpendicular to the principal axis are taken as positive, while the downward distances perpendicular to the principal axis is taken as negative.