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Question
The diagram showed a lens as a combination of one glass block and two prisms. Complete the ray diagram and show the part of the incident ray AB after passing through the lens.
(i) Name of the lens formed by the combination.
(ii) What is the line XX’ called?
(iii) Mark the focus F.
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Solution
The completed ray diagram is shown.
(i) The lens formed by the combination is the convex lens.
(ii) The line XX’ is called the principal axis.
(iii) The focus has been marked by the letter F in the diagram.
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