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The nature of light Reflection Refraction

Index of refraction

Huygens’ Principle Dispersion and Prisms Total Internal Reflection

Light as Particles Tactile Theory (Ancient Greeks)

Emission Theory (al-Haitham)

Newton Light as Waves (w, k)

Huygens

Maxwell Quantum Theory (E = hf)

Photons

srev /5.27w

360teethN

md 7500

st 51005.55.27

7201 w

sm

s

m

t

dc /1097.2

1005.5

750022 8

5

Specular Reflection Diffuse Reflection

11

constantsin

sin

1

2

1

2 v

v

Suppose the sprinters wish to get from point Q on the

beach to point P on the parking lot as quickly as possible.

Which path takes the least time?

1. a

2. b

3. c

4. d

5. e

6. All paths take the same

amount of time.

v

cn

mediumin light of Speed

in vacuumlight of Speed

Going from one medium to another, the frequency of light does

not change but its wavelength does.

1

2

2

1

2

1

2

1

n

n

nc

nc

v

v

If one of the medium’s is vacuum (n=1),

n

n

2211 sinsin nn Snell’s Law of Refraction

h

1

2

12 sinsin

n

n

2

1

23 sinsin

n

n

11

2

1

1

23 sinsinsin

n

n

n

n

h

2cos

hx

sinxd

21

21

2

sincos

h

d

d x

2

1

AC

CA1sin

AC

AD

1sin

ADCA

11

AC

tv 1

1sinAC

tv 2

2sin

2

1

2

1

2

1

sin

sin

nc

nc

v

v

2211 sinsin nn

nn

: angle of deviation

22

dmin

22

min21

d

21 sinsin n

2sin

2sin min n

d

2sin

2sin min

d

n

d

1

4

d 41

2

3

3241

3421

d

d

32

90sinsin 21 nn c

1

2sinn

nc Only for n1 > n2

Critical Angle, c

8.48

752.033.1

1sin

1

2

c

cn

n

For < c: The fish sees above

the water

For = c : The fish sees the

shoreline

For > c : The fish sees the

pond bottom

Retroreflector Periscope Fiber Optic Cable

Reading Assignment

Chapter 36: Image Formation

WebAssign: Assignment 13