Physics · 2025
JEE Main · 22 January 2025, Shift 2 · Q41
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…
A transparent film of refractive index, $\displaystyle 2.0$ 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 $\displaystyle 550$ nm. [Assume that the light is incident nearly perpendicular to the glass surface.]
Official answer
From NTA’s final answer key for this paper.
(1)
137.$\displaystyle 5$ nm
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JEE Main 2025 Physics question, with the answer from NTA’s final answer key. Where our answers come from.