6. OG Refraction of light

Question 1

What is the normal?

Answer 1

90 degrees to the surface + doesn’t refract

Question 2

ray of light > water = ?

Answer 2

slows down + refracts

Question 3

ray of light < water = ?

Answer 3

speeds up + refracts

Question 4

Which lens focuses light?

Answer 4

convex

Question 5

Which lens diffracts light into a spectrum of colours?

Answer 5

prism

Question 6

Which lens lens cause light to diverge?

Answer 6

concave

Question 7

What type of material cause light to refract?

Answer 7

transparent

Question 8

Formula for refractive index?

Answer 8

n = c/cs

(c = speed of light)
(cs = velocity of light in material)

Question 9

What is snell’s law?

Answer 9

When ray of light passes from less dense to more dense, speed change ( slow down) & direction bend toward normal

Question 10

Equation of snell’s law?

Answer 10

n1c1 = n2c2
or
n1sinθ1 = n2sinθ2

theta obviously correlates to the angles n shit okay???

Question 11

Why mirror reflect?

Answer 11

Cuz angle of incidence ig?

Question 12

Light in glass block explanation please?

Answer 12

Material is denser, light slow down and refracts

Question 13

Light in prism explain damn

Answer 13

Blue light refracts more?

Spectrum made and refracts all colours cuz diff wavelengths

Question 14

What happens if the angle of incidence is smaller than the critical angle?

Answer 14

• Most light refracted out of block
• Some light reflected (weak ray)

Question 15

What happens if the angle of incidence is same as critical angle?

Answer 15

• Refracted ray bent through angle of 90° from normal
• Refracted ray weaker than reflected

Question 16

What happens if the angle of incidence is bigger then critical angle?

Answer 16

• No refraction
• Total internal reflection (boundary surface acts like normal mirror)

Question 17

4 things of multimode optical fibres?

Answer 17

1. Core
2. Cladding
3. Buffer
4. Jacket

Question 18

What da core?

Answer 18

• glass/plastic with higher index of refraction than cladding
• Carries the signal

Question 19

What cladding?

Answer 19

• Glass/plastic with lower index of refraction than core
• To allow total internal reflection

Question 20

What buffer?

Answer 20

• Protects fiber from dmg&moisture

Question 21

What jacket

Answer 21

• Holds 1/more fibers in a cable

Question 22

Why multimode fibre more effective short distance than long?

Answer 22

At long, signal get degraded (more spread out) so has to be boosted to prevent output of being discreet

Question 23

Relationship of time taken to travel thru fibre and the angle to axis of ray?

Answer 23

The steeper the angle to the axis, the longer the light has to travel

Question 24

Difference between monomode & multimode optical fibres?

Answer 24

Monomode = 1 light mode
Multimode = multiple light modes

so damn obvious shut up
(was last year me this pathetic ,’:)

Question 25

How can monomode fibres be used at greater distances and still transfer info at greater speed?????????

Answer 25

• 1 single mode
• Reduces data loss cuz overlapping of modes of light
• Light no need reflection so no speed changes ig?