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Snell's Law Calculator
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Snell's Law was named after the scientist Willebrod Snellius who first formulated. This law gives the idea about how the light behaves when it enters two different media.
When light travels from first medium to the second medium, it obeys the Snell's Law which is as below:

The law states that :
1. The incident ray, the refracted ray and the normal to the surface at the point of incidence all lie in one plane.
2. For any two given pair of mediums, the ratio of the sine of the angle of incidence to the sine of the angle of refraction is a constant.

The Snell's Law Formula is given by

$\frac{sin_{\theta_{1}}}{sin_{\theta_{2}}}$ = $\frac{n_{2}}{n_{1}}$ = a Constant = $\mu$.

Where $\theta_{1}$ = Angle of Incidence in First Medium,
$\theta_{2}$ = Angle of Refraction in Second Medium,
$\mu$ = Constant,
n1 = Refractive Index in first medium,
n2 = Refractive Index in second medium.

Snell's Law Calculator helps us to determine the unknown parameter among the above four parameters if any of the three parameters are given.

## Steps for Snell's Law Calculator

Step 1 :

Go through the problem and analyze what are the given parameters and what is the Unknown quantity.

Step 2 :

Use the formula
n1 sin $\theta_{1}$ = n2 sin $\theta_{2}$
substitute the given parameters in this formula and determine the Unknown quantity.

## Problems on Snell's Law Calculator

1. ### If light travels from Air to water with angle of incidence of 300. Calculate its angle of refraction.

Step 1 :

Given that:

Refractive Index of Air n1 =1,
Refractive Index of Water n2 = 1.33,
Angle of incidence $\theta_{1}$= 550

Step 2 :

Use the formula
n1 sin $\theta_{1}$ = n2 sin $\theta_{2}$

Substituting the Values

sin $\theta_{2}$ = $\frac{n_{1} sin \theta_{1}}{n_{2}}$

= $\frac{1 \times sin {30^{\circ}}}{1.33}$

0.727

2. ### A light ray enters in to the optical medium having R.I as 1.5 from air having an angle of Incidence of 400. Calculte its angle of refraction.

Step 1 :

given $\theta_{1}$ = 400,
$\theta_{2}$ = ?,
n1 = 1,
n2 = 1.5

Step 2 :

sin $\theta_{2}$ = $\frac{n_{2} sin \theta_{2}}{sin \theta_{1}}$
= $\frac{1.5 \times sin 40^{\circ}}{1}$
sin $\theta_{2}$ = 0.4967

$\theta_{2}$ = 0.5198