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Question
Object at 2F1 of a convex lens : Image at 2F2 : : Object at F1 : _______
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Solution
Object at 2F1 of a convex lens : Image at 2F2 : : Object at F1 : Image at infinity
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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.
(A) 1, 2 and 4
(B) 1, 3 and 5
(C) 2, 4 and 5
(D) 2, 3 and 4
A ray of light travelling in water emerges into air. Draw a ray-diagram indicating the change in its path.
Draw a labelled ray diagram to show how a ray of light is refracted when it passes:
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Describe the nature of image formed when an object is placed at a distance of 30 cm from a convex lens of focal length 15 cm.
Find the position and nature of the image of an object 5 cm high and 10 cm in front of a convex lens of focal length 6 cm.
A convex lens of focal length 15 cm produces a magnification of +4. The object is placed:
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(c) at less than 15 cm
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Draw neat diagram to show the
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A lens always forms an image between the object and the lens.
A lens always forms an image between the object and the lens.
Why do we say that the ‘2F’ and ‘F’ points of a convex lens can be regarded as a sort of ‘turning points’ as far as the nature of the image formed by it is concerned?
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