An object is placed in front of a convex mirror. Which one of the following statements is correct?
- A.It will never form an inverted image.
- B.The image moves towards the focus when the object moves towards the mirror.
- C.Depending on the position of the object with respect to the mirror, the image can be inverted and real.
- D.The size of the image becomes larger than that of the object when the object is placed at a distance equal to half the focal length.
Correct answer
Explanation
The correct answer is A, It will never form an inverted image. For a real object anywhere in front of it, a convex mirror always gives a virtual, erect and diminished image.
A convex mirror bulges outward, so the rays it reflects spread apart and never meet in front of it. They only seem to come from a point behind the mirror, between its pole and its focus. When the object is very far away, the image sits at the focus as a tiny point; as the object comes closer, the image moves from the focus towards the pole and grows, but it always stays smaller than the object. This wide, upright view is why convex mirrors are used as rear-view mirrors in vehicles.
B is wrong because the image moves away from the focus, towards the pole, as the object approaches. C is wrong because a convex mirror never forms a real, inverted image of a real object. D is wrong because the image is always smaller than the object.
Exam tip: convex mirror image always virtual, erect, diminished, between pole and focus.
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