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प्रश्न
Fig shows a lens as a combination of a glass block and two prisms.
(i) Name the lens formed by the combination.
(ii) What is the line XX' called?
(iii) Complete the path of the incident ray PQ after passing through the lens.
(iv) The final emergent ray either meets XX' at a point or appears to come from a point on XX'. Label it as F, What is this point called?
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उत्तर
(i) Concave lens.
(ii) The line XX' called the principal axis.
(iii)
(iv) The final emergent ray will appear to meet XX' at a point called its second focus of the lens.
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