Question

The lens A produces a magnification of, − 0.6 whereas lens B produces a magnification of + 0.6.
(a) What is the nature of lens A?
(b) What is the nature of lens B?

Answer 1

​(a) Negative magnification shows that the image is real and inverted. Therefore, it's a convex lens.
​(b) Positive magnification shows that image is virtual and erect. The lens can be concave or convex in nature. However, a convex lens always forms a magnified virtual image. According to the given magnification, the size of the image is smaller than the size of the object. Therefore, the lens must be concave in nature.