Question

For what distance is ray optics is good approximation when the aperture is 4 mm and the wavelength of light is 400 h m? (1) 30 m (2) 18 m (3) 40 m (4) 24 m

Answer 1

Explanation:

Solution :

ZF=a2λ

=(4×10−3)2400×10−9

=16×10−64×10−7=40m