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