Question

A person wishes to distinguish between two pillars located at a distance of 11 km. What should be the minimum distance between these pillars (resolving power of normal human eye is 1')?

• A. 1 m
• B. 3.2 m
• C. 0.5 m
• D. 5 m

Answer 1

Answer: (B)

3.2 m

Resolving power is given by the distance between two objects to be distinguished per unit distance of objects from the object distinguishing them.

Hence,$\theta =\frac{d}{D}$

Hence,$d=\theta D=\frac{1}{60}\times \frac{\pi }{180}\times 110000=3.2m$