Question

The reflection of light from the thin film of thickness t as shown in the figure appears violet (400nm) when viewed from above. This means the two rays reflecting off of the two surfaces interfere constructively. t is the minimum thickness. The dark grey material has a higher index of refraction than the light grey with the white being air. For what minimum thickness relative to t would it need to be for the film to now appear red (700nm)

answer is E) 1.75t

please show all steps

The reflection of light from the thin film of thickness t as shown in the figure appears violet (400 nm) when viewed from above. This means the two rays reflecting off of the two surfaces interfere constructively. t is the minimum thickness. The dark grey material has a higher index of refraction than the light grey with the white being air. For what minimum thickness relative to t would it need to be for the film to now appear red (700 nm)? a. 0.57 t b. 2.0 c. 1.5 t d. 1.0t e. 1.75 t t

Answer 1

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