Question

If light waves change speed as they pass from one medium into another at an angle, the light will be ____.

a. diffracted
c. separated
b. reflected
d. refracted

Answer 1

The question is asking to choose among the following choices that states what happen to the light if light waves change speed as they pass from one medium into another at an angle, base on my research, the answer would be letter D. refracted. I hope you are satisfied with my answer and feel free to ask for more 

Answer 2

The correct answer is
d. refracted

In fact, refraction occurs when light travels from one medium to another, and when it crosses the interface between the two mediums, light changes both its direction and its speed.

There is a mathematical relationship which allows us to calculate how much the direction and the speed change. It is called Snell's law, and it is the following:

`n_1 \sin \theta_1 = n_2 \sin \theta_2`
where n1 and n2 are the reffractive index of the first and second medium, while
`\theta_1, \theta_2` are the angle of the light in the first and the second medium, measured with respect to the perpendicular to the interface between the two mediums.

The refractive index, instead, measure how much the speed of light changes in a medium. It is defined as follows:

`n= (c)/(v)`
where c is the speed of light in vacuum and v is the speed of light in that medium. If we know c and n, we can find the speed of light in that medium, v.