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Question
Give two circumstances in which a concave mirror can form a magnified image of an object placed in front of it. Illustrate your answer by drawing labelled ray diagrams for both.
Solution
The two circumstances in which a concave mirror can form a magnified image of an object that is placed in front of it are:
- When an object is placed between the pole and the focus of a concave mirror, the image formed is virtual, erect and magnified, as shown in the figure. Here, the object AB is placed between the pole and the focus of a concave mirror. Its image A'B' is formed behind the
mirror and is virtual, erect and magnified.
- When an object is placed between the centre of curvature and the focus of a concave mirror, the image formed is real, inverted and enlarged, as shown in figure 2. Here, the object AB is placed between the centre of curvature and the focus of a concave mirror. Its image A'B' is formed beyond the centre of curvature and is real, inverted and enlarged.
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