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Question
State the condition of the following:
A lens has both its focal lengths equal.
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Solution
If the medium on both sides of the lens is same, the first and second focal lengths are equal.
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RELATED QUESTIONS
In the following figure (a) and (b), F1 and F2 are positions of the two foci of thin lenses. Draw the path taken by the light ray AB after it emerges from each lens.
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| (a) |
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