A point source S ic centered infront of a 70cm wide plane  mirror .A man starts  walking from d source along a line parallel to d mirror. find d max distance tat can b walked by man without losing sight of d image of source.

I think the answer is 70cm from the source.

Look at the figure. The last reflection of a ray coming out from the source S can take place only from the tip of the mirror and by similarity and congruence of triangles, you can easily see that maximum distance from the source = H/2 + H/2 = H

Hope I am correct.

yeah rit.......

and remembr 1 more thg to see a complete image himself h b4 a mirror one needs to hve a mirror of height h/2

this is derived as tarin did........

Cheers!!!!!!