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Index of Refraction of Various Household Liquids

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Introduction

Index of refraction values (n) are numerical index values that are expressed relative to the speed of light in a vacuum. The index of refraction value can tell you the optical density of the material. It is a numerical value which indicates the number of times that a light wave would be in that material rather than in a vacuum. The index of refraction is defined as the speed of light in vacuum divided by the speed of light in the medium.

n = c/v

Procedure

The index of refraction can be calculated by using the angle that light bends when traveling from one liquid to another liquid. Snell's law gives the relation between the angles θ1 and θ2:

n1/n2 = sin θ2/sin θ1

The paper and procedure we used can be found on page 2 of this pdf.

The indices of refraction of all the liquids are given by the slope on each graph.

Results

Glycerin: n = 1.367

angle of refraction (°) angle of incidence (°) sine of angle of refraction sine of angle of incidence (°)
5 9 0.0871557427477 0.15643446504
10 17 0.173648177667 0.292371704723
15 23 0.258819045103 0.390731128489
20 31 0.342020143326 0.51503807491
25 39 0.422618261741 0.62932039105
30 49 0.500000000000 0.754709580223
35 55 0.573576436351 0.819152044289
40 66 0.642787609687 0.913545457643

All Purpose Cleaner: n = 1.293

angle of refraction (°) angle of incidence (°) sine of angle of refraction sine of angle of incidence (°)
5 8 0.0871557427477 0.13917310096
10 14 0.173648177667 0.2419218956
15 22 0.258819045103 0.374606593416
20 28 0.342020143326 0.469471562786
25 36 0.422618261741 0.587785252292
30 42 0.500000000000 0.669130606359
35 51 0.573576436351 0.777145961457
40 60 0.642787609687 0.866025403784
45 69 0.707106781187 0.933580426497

Degreaser: n = 1.377

angle of refraction (°) angle of incidence (°) sine of angle of refraction sine of angle of incidence (°)
5 7 0.0871557427477 0.121869343405
10 15 0.173648177667 0.258819045103
15 22 0.258819045103 0.374606593416
20 29 0.342020143326 0.484809620246
25 37 0.422618261741 0.601815023152
30 44 0.500000000000 0.694658370459
35 54 0.573576436351 0.809016994375
40 63 0.642787609687 0.891006524188

Shower Gel: n = 1.51

angle of refraction (°) angle of incidence (°) sine of angle of refraction sine of angle of incidence (°)
5 9 0.0871557427477 0.15643446504
10 15 0.173648177667 0.258819045103
15 19 0.258819045103 0.325568154457
20 29 0.342020143326 0.484809620246
25 36 0.422618261741 0.587785252292
30 43 0.500000000000 0.681998360062
35 53 0.573576436351 0.798635510047
40 63 0.642787609687 0.891006524188
45 72 0.707106781187 0.951056516295

Baby Wash: n = 1.26

angle of refraction (°) angle of incidence (°) sine of angle of refraction sine of angle of incidence (°)
5 8 0.0871557427477 0.13917310096
10 15 0.173648177667 0.258819045103
15 22 0.258819045103 0.374606593416
20 30 0.342020143326 0.500000000000
25 37 0.422618261741 0.601815023152
30 43 0.500000000000 0.681998360062
35 51 0.573576436351 0.777145961457
40 61 0.642787609687 0.874619707139
45 70 0.707106781187 0.939692620786
50 80 0.766044443119 0.984807753012

Kristina Arthurs, Nadia Christopher, Monique Anthony, Whitney Daniel -- 2005