Physics-
General
Easy
Question
A point source of light B is placed at a distance L in front of the centre of a mirror of width d hung vertically on a wall. A man walks in front of the mirror along a line parallel to the mirror at a distance 2L from it as shown. The greatest distance over which he can see the image of the light source in the mirror is
- d/2
- d
- 2d
- 3d
The correct answer is: 3d
According to the following ray diagram 
and 
Similarly
so 
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