# data[].attributes.headline
What happens to the speed of light after it enters a substance

# data[].attributes.subject
What happens to the speed of light after it enters a substance

# data[].attributes.body
If light travels from a lower index of refraction to a higher index of refraction
then the speed of light decreases
(ex. light travelling from air to water n1=1 n2=1.33)

If light travels from a higher index of refraction to a lower index of refraction then the speed of light increases
(ex. light travelling from diamond to air n1=2.42 n2=1

# data[].attributes.body
Find θ1
Find θ2
Find n1

use the following equation to find θ2 rearrange it if necessary:

n1sin(θ1)=n2sin(θ2)

n2= n1sin(θ1)/sinθ2)

# data[].attributes.body
find θ1 or the angle of incidence

find n1 or the index of refraction of the first substance

Find n2 or the index of refraction of the second substance

use the following equation to find θ2 rearrange it if necessary:

n1sin(θ1)=n2sin(θ2)

θ2= sin^-1(n1sin(θ1)/n2)

# data[].attributes.headline
if the total internal reflection occurs at a glass to air surface: 

# data[].attributes.subject
if the total internal reflection occurs at a glass to air surface: 

# data[].attributes.body
There is an angle of reflection

There is no angle of refraction

# data[].attributes.headline
Give three examples of electromagnetic radiation?

# data[].attributes.subject
Give three examples of electromagnetic radiation?

# data[].attributes.body
light makes up the visible spectrum