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Question
State the position of object, position of image, nature of image when: Convex lens is used as objective lens of astronomical telescope.
Solution
Object is at infinity.
Image is formed at F2 on the other side of lens. Image is real; inverted and almost diminished to a point.
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RELATED QUESTIONS
A student is using a convex lens of focal length 18 cm to study the image formation by it for the various positions of the object. He observes that when he places the object at 27 cm, the location of the image is at 54 cm on the other side of the lens. Identify from the following diagram the three rays that are obeying the laws of refraction and may be used to draw the corresponding ray diagram.
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