Question

Q. A person wants to see two pillars distant 11 km as separate and distinct. the distance between the pillar must be approximately
1) 0.25 m
2) 3 m
3) 1 m
4) 0.5 m

Answer 1

Dear Student,

$$\begin{gathered} \mathrm{Resolving}\mathrm{power}\mathrm{of}\mathrm{eye}={\left(\frac{1}{60}\right)}^0 \\ \mathrm{Resolving}\mathrm{power}\mathrm{of}\mathrm{eye}=\frac{\mathrm{\pi }}{180\times 60}\mathrm{rad} \\ \mathrm{Let}\mathrm{d}\mathrm{be}\mathrm{the}\mathrm{required}\mathrm{distance}, \\ \frac{\mathrm{\pi }}{180\times 60}=\frac{\mathrm{d}}{11000} \\ \mathrm{d}=\frac{\mathrm{\pi }\times 11000}{180\times 60}=3.2\approx 3\mathrm{m} \end{gathered}$$