Magnification values and signs produced by a Lens & their implication | Lens Magnification rules
Let’s see what the value and sign of the magnification of a lens tell us about the type of lens and image formed.
1) If the magnification ‘m’ has a positive value, the image is virtual and erect. And if the magnification ‘m’ has a negative value, the image will real and inverted.
2) A convex lens can form virtual images as well as real images, therefore, the magnification produced by a convex lens can be either positive or negative.
3) A convex can form images which are smaller than the object, equal to the object, or bigger than the object, therefore magnification ‘m’ produced by a convex lens can be less than 1, equal to 1, or more than 1.
4) A concave lens, however, forms only virtual images, so the magnification produced by a concave lens is always positive.
5) A concave lens forms images that are always smaller than the object, so the magnification ‘m’ produced by a concave lens is always less than 1.
Related Posts you can refer to understand the rules of magnification by spherical lenses.
sign convention for spherical lenses
what is magnification in context with a lens?
ray diagrams of convex and concave lenses
convex lens – rules of the images formed