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Question
A ray of light after refraction through a lens emerges parallel to the principal axis of the lens. The incident ray either passes through ______.
Options
its optical centre
its first focus
its second focus
its centre of curvature of the first surface
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Solution
A ray of light after refraction through a lens emerges parallel to the principal axis of the lens. The incident ray either passes through its first focus.
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RELATED QUESTIONS
In figure, (a) and (b), F1 and F2 are the two foci of thin lenses and AB is the incident ray. Complete the diagram to show the path of the ray AB after refraction through each lens.
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