The given figure shows an object and its image formed on a screen by a convex lens.

If the convex lens is replaced by a concave lens of equal focal length, the image will

Only real images can be obtained on a screen. Concave lenses cannot form real images. The image formation of an object placed between the focus, F and the centre of curvature, 2F of a concave lens is shown in the following figure.

Since the image is erect, it will be a virtual image. Hence, it cannot be obtained on a screen. Thus, the image that is formed by the convex lens will disappear from the screen when the lens is replaced by a concave lens.