Question

A point source of light $S,$ placed at a distance $60cm$ infront of the centre of a plane mirror of width $50cm$, hangs vertically on a wall. A man walks infront of the mirror along a line parallel to the mirror at a distance $1.2m$ from it (see in the figure). The distance between the extreme points where he can see the image of the light source in the mirror is $\dots \dots \dots .cm$.

Answer 1

Answer: 150

$\tan \theta =\frac{25}{60}=\frac{x}{180}$
$x=75cm$
so distance between extreme point $=2x=2\times$
$75=150cm$