Which of the following types of images can be obtained on a screen?
(a) Real and enlarged
(b) Real and diminished
(c) Virtual and enlarged
(d) Virtual and diminished
Options:
(A) Both (c) and (d)
(B) Both (a) and (d)
(C) Both (a) and (b)
To determine which images can be projected onto a screen, evaluate how optical images are formed:
1. Real Images
Real images are formed by the actual convergence of light rays after reflection or refraction. Because physical light rays intersect at the image point, these images can always be captured or projected onto a physical screen.
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Real and enlarged: Formed when an object is placed between the focus ($F$) and center of curvature ($C$) of a concave mirror, or between $F_1$ and $2F_1$ of a convex lens.
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Real and diminished: Formed when an object is placed beyond the center of curvature ($C$) of a concave mirror, or beyond $2F_1$ of a convex lens.
Notice how light rays cross in the ray diagram below to form a real image:
2. Virtual Images
Virtual images are formed where light rays only appear to diverge from a point behind the mirror or lens. Because no light actually passes through that location, virtual images cannot be focused onto a screen (they can only be viewed by looking into the optical element directly).
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Virtual and enlarged (e.g., concave mirror with object inside focus) –> Cannot be caught on a screen.
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Virtual and diminished (e.g., convex mirror) –> Cannot be caught on a screen.
Final Answer
Since only real images can be obtained on a screen, both (a) Real and enlarged and (b) Real and diminished are correct.
Correct Option: (C) Both (a) and (b)
