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Question
"A lens can form a magnified erect image as well as magnified inverted image of an object placed in front of it." State the nature of this lens and draw ray diagrams to justify the above statement. Mark the positions of O, F and 2F in the diagram.
Solution
The lens is a convex in nature. Thus, it is a convex lens.
When the object is placed between the focus F1 and optical centre O a magnified erect image is formed as shown below.
When the object is placed between the focus F1 and 2F1 a magnified inverted image is formed as shown below.
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| 1 | –100 | +25 |
| 2 | –60 | +30 |
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