Read to find common medium refractive index values
Vacuum : 1
Air: 1.000293
Water (Room Temperature: 20 deg C approx.): 1.333
Ethanol: 1.36
Ice: 1.31
Acrylic: 1.49
Glass (Window): 1.52
Diamond: 2.419
Calculators
Angle of Refraction (given the indices)
Enter the refraction indices and angle of incidence to calculate the angle of refraction.
Formula:
θ2=sin−1(n2n1sin(θ1))
Input:
The refractive index of medium 1,
n1
:1.333
The refractive index of medium 2,
n2
:1
The Angle of Incidence in degrees (
θ1
),
AOI
:20deg
Output:
Using the formula denoted above, we can substitute the inputs to get:
The Angle of Refraction (
θ2
or
AOR)
:27.12deg
Angle of Incidence (given the indices)
Enter the refraction indices and angle of refraction to calculate the angle of incidence.
Formula:
θ1=sin−1(n1n2sin(θ2))
Input:
The refractive index of medium 1,
n1
:1.333
The refractive index of medium 2,
n2
:1.000293
The Angle of Refraction in degrees (
θ2
) or
AOR
:50deg
Output:
Using the formula denoted above, we can substitute the inputs to get:
The Angle of Refraction in degrees (
θ2
or
AOI)
:35.09deg
Refractive Index of Medium 1 (given the angles)
Enter the angle of refraction, the angle of incidence and refraction index of medium 2 to calculate the refraction index of medium 1.
Formula:
n1=sin(θ1)n2sin(θ2)
Input:
The Angle of Incidence in degrees (
θ1
) or
AOI
:50deg
The Angle of Refraction in degrees (
θ2
) or
AOR
:20deg
The refractive Index of medium 2,
n2 (1)
:1.000293
Output:
Using the formula denoted above, we can substitute the inputs to get:
The refractive index of medium 1,
n1 (2)
:0.446606
Refractive Index of Medium 2 (given the angles)
Enter the angle of refraction, the angle of incidence and refraction index of medium 1 to calculate the refraction index of medium 1.
Formula:
n2=sin(θ2)n1sin(θ1)
Input:
The Angle of Incidence in degrees (
E=mc^2
) or
AOI (1)
:50deg
The Angle of Refraction in degrees (
θ2
) or
AOR (2)
:20deg
The refractive index of medium 1,
n1 (3)
:1.000293
Output:
Using the formula denoted above, we can substitute the inputs to get:
The refractive index of medium 2,
n2 (3)
:2.24042
Critical Angle (using the indices)
When the AOR value in the "Finding Angle of Refraction" section shows "NaN", it means that the angle of incidence is greater than the critical angle and the wave now undergoes internal reflection rather than refraction.
Formula:
θc=sin−1(n1n2)
Input:
The refractive index of medium 1,
n1
:1.333
The refractive index of medium 2,
n2
:1
Output:
Using the formula denoted above, we can substitute the inputs to get:
Critical Angle,
θc
or
CA
:48.61deg
Velocity of the waves in each medium (using the indices)
Enter the indices and use the relationship on the left to find
v1
and
v2
. The variable
c
represents the speed of light.
Formula:
vm=nmc
Input:
The refractive index of medium 1,
n1
:1
The refractive index of medium 2,
n2
:1
Speed of light through vacuum in m/s,
c
:300000000m/s
Output:
Using the formula denoted above, we can substitute the inputs to get:
The velocity of the wave in m/s in medium 1,
v1
:3.0E8m/s
The velocity of the wave in m/s medium 2,
v2
:3.0E8m/s
Wavelength of the waves in each medium (using the indices)
Enter the indices and use the relationship on the left to find
λ1
and
λ2
. Before you begin, ensure you know the nature of the wave since the
λ0
value represents the wavelength of wave in vacuum. But all waves have different wavelengths in vacuum. (For example,
λ0
of red light in vacuum is approx. 700 nm).
Formula:
λm=nmλ0
Input:
The refractive index of medium 1,
n1
:1
The refractive index of medium 2,
n2
:1
The wavelength of the wave in vacuum,
λ0
:600nm
Output:
Using the formula denoted above, we can substitute the inputs to get:
The wavelength of the wave in medium 1,
λ1
:600.0nm
The wavelength of the wave in medium 2,
λ2
:600.0nm
Related Resources
The values required from your end depend on the calculator you use, but all calculators revolve around the following parameters:
θ1,θ2,n1,n2
. If another type of variable is provided, look at our other calculators: