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Question
What type of lenses are used in spectacles worn by an old lady for knitting?
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Solution
A converging lens of suitable focal length is used in the spectacles worn by an old lady for knitting.
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RELATED QUESTIONS
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In the diagram below, XX’ represents the principal axis, O the optical centre and F the focus of the lens. Complete the path of rays A and B as they emerge out of the lens.
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| (a) | (b) |
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State the condition of the following:
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(i) Draw the outline ofthe lens L used and Named it.
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A lens used as a magnifying glass
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What principles have you used in completing the diagram?
