Physicshard · Past Paper
A convex lens forms a real image of a point object on the principal axis. If the upper half of the lens is painted black:
AHalf the image disappears
BFull image is formed but brightness reduces
CImage shifts downwards
DNo image is formed
✓ Correct Answer: B — Full image is formed but brightness reduces
Every part of the lens forms a complete image; reducing the area only reduces the amount of light (intensity).
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