Question

(33 Question 19 1 A very thin film of transparent oil of refractive index_1.40 floats on a smooth hody of water of refractive index 1.33. Above the oil is air, Green light of wavelength 520 nm (in air) is incident normally on to the oil from above." green light, A=520 nm air oil, = 1.40 water, n 1.33 Do light waves reflected at the top of the oil suffer a phase inversion upon reflection ? Give a (a) Yes . reason Do light waves reflected at the bottom of the oil suffer a phase inversion upon reflection ? Give a reason. (b) Calculate the wavelength of the light in the oil. (c) When the film is viewed from above, bright reflection of green light is observed, except at the edges where the thickness of the film approaches zero. (d) Explain why no reflection is observed at the edges of the film. Show that a film of thickness 93 nm will produce bright reflection. 20x 371メl-1
part d and e i want a further explanation

Answer 1

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