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Question
A student obtained a sharp image of the grills of a window on a screen using a concave mirror. His teacher remarked that for getting better results a well lit distant object (preferably the sun) should be focussed on the screen. What should be done for this purpose?
(A) Move the screen slightly away from the mirror
(B) Move the mirror slightly towards the screen
(C) Move the screen and the mirror away from the object
(D) Move the screen and the mirror towards the object
Solution
As the image distance is increased, the object distance would decrease and thus mirror-screen distance should be decreased. The mirror should be moved towards the screen.
The Correct Answer is B
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| A | B | C | D |
