Reflection/Refraction [P]

Question 1

Define the term reflection.

Answer 1

The bouncing back of the light from a surface.

Question 2

Define the term refraction.

Answer 2

Bending up of the light when it goes from one substance (medium) to another. This happens due to the change of speed.

Question 3

On a reflection diagram, name all the different rays (lines) that are shown.

Answer 3

Incident ray hitting the mirror, Normal line drawn 90 degrees to the mirror, Reflected ray from the normal line, same angle as incident ray

Question 4

Describe the change of speed and bending in refraction.

Answer 4

When light travels from a less dense to a more dense medium, it will slow down and bend towards the normal.

Question 5

Define the term Critical Angle.

Answer 5

The Angle of Incidence where the Angle of Refraction is 90 Degrees.

Question 6

The formula for critical angle is sin(C) = 1/n. What does C and n represent?

Answer 6

C = critical angle
n = Refractive Index

Question 7

What is “TIR” and what are the requirements for it to happen?

Answer 7

Total Internal Reflection.
- Light must travel from more dense to less dense
- Angle of incidence should be greater than the critical angle

Question 8

How does the glass cladding contribute to fibre optic cables?

Answer 8

Allows total internal reflection
Reduced energy loss
There are fewer reflections