Question

Why do we take magnification negative

Answer 1

Hii dear here is your answer


Using the Gaussian form of the lens equation, a negative sign is used on the linear magnification equation as a reminder that all real images are inverted. If the image is virtual, the image distance will be negative, and the magnification will therefore be positive for the erect image.


Hope it's help u

Answer 2

ans )
If the image of object is inverted ( below principal Axis) then the magnification of the image is taken as negative