U2.2 Refraction

Question 1

What happens when light travels from a less dense medium to a more dense medium

Answer 1

Light slows down and bends towards the normal

Question 2

What happens when light travels from a more dense to a less dense medium

Answer 2

Light speeds up and bends away from the normal

Question 3

I what happens if a ray of light hits the boundary at 90°

Answer 3

No refraction occurs

Question 4

What is snells law

Answer 4

When light passes from one medium into another, the ratio of the sine of the angle of the incidence to the sine of the the angle of refraction is a constant.

Question 5

What is the equation for snells law

Answer 5

Sin i / Sin r = n

Question 6

What is the refractive index

Answer 6

The speed of light in the two media through which the light travels

Question 7

How do you find the refractive index

Answer 7

n = speed of light in medium 1 / speed of light in medium 2

n = c1 / c2

Question 8

What is the relationship between snells equation and the equation for refractive index

Answer 8

Sin i / Sin r = C1 / C2

Question 9

What is the absolute refractive index

Answer 9

When light passes from a vacuum (or air) into another medium then the refractive index is known as the absolute refractive index.

Question 10

What is the calculation for the absolute refractive index

Answer 10

₁n₂ = n₂ / n₁

Question 11

What is the critical angle

Answer 11

The angle of incidence which results in an angle of refraction equal to 90° is called the critical angle

Question 12

What is total internal reflection

Answer 12

When a ray of light travels from a more dense to a less dense medium, it is refracted away from the normal. As the angle of incidence is increased, the angle of refraction increases until it reaches 90°. Any further increase in I results in the ray undergoing total internal reflection.