JEE Main 2025 Physics question

A transparent film of refractive index, 2.0 is coated on a glass slab of refractive index, 1.45. What is the minimum thickness of transparent film to be coated for the maximum transmission of Green light of wavelength 550 nm. [Assume that the light is incident nearly perpendicular to the glass surface.]

• (1)94.8 nm
• (2)68.7 nm
• (3)137.5 nmCorrect
• (4)275 nm