Two parallel pillars are 11 km away from an observer. The minimum distance between the pillars so that they can be seen separately will be

As limit of resolution of eye is 160∘, the pillars will  be seen distinctly if θ>160∘  i.e. 는 dx>160×π180 ⇒d>π×x60×180 ⇒d>3.14×11×10360×180⇒d>3.2m