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A student focuses the image of a well il...

A student focuses the image of a well illuminated distant object on a screen using a convex lens. After that the gradually moves the object towards the lens and each time focuses its image on the screen by adjucting the lens.
(a) In which direction -towards the screen or away from the screen, does he move the lens ?
(b)What happens to the size of the image-does it decrease or increase ?
(c) What happens to the image on the screen when he moves the object very close to the lens ?

Text Solution

Verified by Experts

(a) He moves the screen away from lens to focus the object.
(b) The size of the image increases.
(c ) When the object is places very close to the lens, then image will be formed on the screen. As now image formed is erect and virtual.
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