testing refractive indexes in solution sam benkelman

Testing Refractive Indexes in Solution

Sam Benkelman

Introduction--AbstractThe refractive index, n, of a substance determines how much it bends light upon entrance in a vacuum. Directly related to density, n of solid substances can be measured in a variety of ways. This experiment designs and proofs a new method with which to test the refractive indexes of solutions.

Background--Refractionhttp://www.freezeray.com/flashFiles/Refraction1.htm

http://www.freezeray.com/flashFiles/Refraction2.htm

Background--Refraction● Snell’s Law

n1sin𝜭1 = n2sin𝜭2

Setup

Tank Laser

Wall

n1

n2

Setup

Perpendicular

Distance P

Distance D

Width W

𝞱1

��2

Procedureindex of air is virtually 1

n2 = sin𝜭1 / (sin(tan-1(P/W)))

P = Wtan(sin-1(sin𝜭1 /n2 ))

Procedure● Set testing tank in place● Turn on laser, mark initial endpoint● Pour in solution● Mark final endpoint● Measure distance P

DataSubstance Distance P (mm) Calculated Index Given Index

H2O (baseline) 68 1.327 1.33--1.34

NaCl, 2 M 66 1.351 1.38

Ethyl Alcohol 64 1.376 1.36

Soybean Oil 54 1.535 1.47

Conclusion● In a perfect world…

o Results look hopefulo Testing method could be practical on a larger scale

Improvements● BETTER MEASUREMENTS

References"‘Cloaking’ Device Uses Ordinary Lenses to Hide Objects across Range of Angles."

NewsCenter. N.p., n.d. Web. 08 Jan. 2015.

"Maxwell's Equations." Maxwell's Equations. N.p., n.d. Web. 10 Jan. 2015.

Fried, Stephen D. "Calculations of the Electric Fields in Liquid Solutions." The Journal of Physical Chemistry. N.p., n.d. Web. 11 Jan. 2015.