A convex lens forms a real image of an object. If the lower half of the lens is covered, the image will: MCQ with Answer and Explanation

A convex lens forms a real image of an object. If the lower half of the lens is covered, the image will:
A. Become virtual
B. Disappear completely
C. Be fainter but complete
D. Be half-formed
Answer: Option C
Solution (By JKSSB Mock Tests)
Covering part of a lens reduces the amount of light reaching the image, making it fainter, but the entire image is still formed because light from each object point can pass through the uncovered portion and converge to the corresponding image point. Image position, size, and nature remain unchanged. Memory aid: 'Partial lens coverage ⇒ reduced intensity, not partial image'. This conceptual question tests understanding of image formation principles, commonly featured in competitive exams to identify misconceptions about ray optics. Always recall that every point on lens contributes to entire image.

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