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Question
A student has to determine the focal length of a concave mirror by obtaining the image of a distant object on a screen. For getting best result he should focus
(A) a distant tree or an electric pole
(B) a well-illuminated distant building
(C) well-lit grills of the nearest window
(D) a burning candle laced at the distant edge of the laboratory table
Solution
In order to determine the focal length of a concave mirror, the student should focus on a distant tree or an electric pole.
The Correct Answer is A
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