Question

< Homework #9 Problem 17.60 MC 7 of 9 Constants A laboratory dish, 30 cm in diameter, is half filled with a glucose/water solution. One at a time, 0.50 L drops of oil from a micropipette are dropped onto the surface of the solution, where they spread out into a uniform thin film. As more drops are added, the intensity of 620 nm light reflected from the surface decreases. The intensity reaches a minimum after a total of 15 drops have been added. In all questions, assume that the oil's index of refraction is smaller than the glucose/water solution's index. Previous Answer Correct PartC What is the index of refraction of the oil Express your answer using three significant figures View Available Hint(s) u 0.29 Submit Previous Answers X Incorrect Try Again Provide Feedback Next >

Answer 1

volume of 13 drops = 15 x 0.5 x10-6 L

V= 7.5 x 10-9 m3

area of dish A is

A = pi r^{2}

if thickness of the film is t

V= At

t = V/A = 1.06 x 10^-7 m

2nt = lambda /2

n is the refractive index

n = lambda /4t

n = 1.46