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Question
Complete the following diagram and state what happens to the ray of light after refraction through the lens.
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Solution
A ray of light goes undeviated through the optical centre of a lens, whether convex or concave.
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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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(i) A rectangular block of glass.
(ii) A 600 glass prism.
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(e) Fig. represents a stone S at the bottom of a pond of water. Using the two rays, as shown, complete the ray diagram to show where the image of the stone appears when viewed from E.
(f) What is a''mirage'? Explain with the help of a diagram.
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