question_answer

Figure shows a cubical room ABCD with the wall CD as a plane mirror. Each side of the room is 3m. We place a camera at the midpoint of the wall AB. At what distance should the camera be focussed to photograph an object placed at A

A)             1.5 m

B)             3 m

C)             6 m

D)            More than 6 m

Correct Answer: D

Solution :

                   According to the following figure distance of image I from camera \[=\sqrt{{{(6)}^{2}}+{{(1.5)}^{2}}}=6.18\,m\]