Blue light ( $\lambda$_v_ac = 440 nm )shines onto a puddle of water (n_water = 1.33).There is a thin layer of oil (n = 1.47)on top of this water.What is the minimum thickness of the oil if there is constructive interference for the light?

Question

Quizplus · Accepted Answer

The correct answer is A because the minimum thickness of the oil for constructive interference is given by:$$t = \frac{\lambda}{4n} = \frac{440 	ext{ nm}}{4(1.47)} = 74.8 	ext{ nm}$$

Blue Light λ\lambdaλ vac = 440 Nm )Shines onto a Puddle of Water

Blue Light $\lambda$ _v_ac = 440 Nm )Shines onto a Puddle of Water