1) Assuming human pupil to have radius of 0.25cm and a comfortable viewing distance of 25cm , the minimum separation between two objects that human eye can resolve at 500 nm wavelength is A) 1μm B) 30μm C) 100μm D) 300μm Answer: Option BExplanation: We can write receiving angle of nacked eye as θ=1.22λD Where, D is the diameter of eye lens. or Y25×10−2=1.22×500×10−90.25×2×10−2 Y=30×10−6m=30μm