A convex lens can form which types of images depending on the object distance?

• A. Only real images.
• B. Both real and virtual images.
• C. Only virtual images.
• D. No image.

Answer: (B)

A convex lens can form real or virtual images depending on where the object sits relative to the focal length. When the object is farther from the lens than the focal length, the lens bends the light so the rays actually converge on the other side, producing a real image. This image is typically inverted and can be projected onto a screen; its size changes with distance (smaller than the object when the object is beyond 2f, larger when between f and 2f, equal at 2f, and moving toward infinity as the object approaches f). When the object is closer to the lens than the focal length, the rays exit the lens as if they are diverging, so tracing them backward shows they come from a point on the same side as the object—giving a virtual image that is upright and magnified and cannot be projected. So a convex lens can form both real and virtual images depending on the object distance.