Physics

APPL
IEDPHY
SICS

2MARKSQUES
TIONBANK




1

, UNI
T-I:
WAVEOPTI
CS

In
terfe
ren c
e-Pr i
nci
pleo fsupe
rposi
ti
on–I nter
fere
nceofl i
ght–I nt
erfere
nceb ydiv
isi
onof
wave
frontanda mpli
tude-In
terfer
enc
einthinfil
ms(Refle
cti
onGe o
me t
ry)–Color
sint h
infil
ms
–Newton’
sRi ngs–De t
erminat
ionofwavel
engt
ha ndref
ract
ivein
dex–Appli
cat
ion
s.
Dif
frac
tion-Intro
ducti
on–Fr esnela
ndFraunhof
erd i
ffr
acti
on–Fr aun
hoferdiff
ract
iondueto
si
ngl
esli
t ,doub
lesli
tandN- s
li
ts(qua
lit
ati
ve)–Grati
ngspect
rum–Appli
cati
ons
.
Pol
ari
zati
o n-Intr
oduc
tion–Ty pesofp ol
ari
zati
on–Po la
riz
ati
onb yrefle
cti
on,refr
acti
onand
dou
blerefract
ion-Nicol
’sPri
sm-Ha lfwav
ea ndQuart
erwaveplat
es–Appli
cat
ion
s.

1
.Wh
ati
sme
antb
yopt
ics
?
An
swe
r:Op
tic
sist
heb
ran
cho
fth
eph
ysi
cs
,wh
ichd
eal
swi
thn
atu
re,p
rop
ert
ies
,ge
ner
ati
on,a
nd
p
rop
aga
tio
nofl
ig
hta
ndi
tsi
nte
rac
ti
onwi
thma
tte
r.

2
.De
fin
ege
ome
tri
corr
ayo
pti
cs?

An
swe
r:I
tisa
ssu
medt
hatl
ig
htt
rav
elsi
nst
rai
ghtl
in
esa
ndwee
xpl
ai
nth
eima
gesa
ref
orme
d
b
ymi
rr
ors
,pr
is
m,l
ens
ese
tc.
,byg
eome
tri
calc
ons
tru
cti
ons
,wi
tho
utc
ons
ide
rin
gth
ena
tur
eof
l
ig
ht.
3.
Def
ineph
ysi
calo
pti
cso
rwa
veo
pti
cs?
An
swe
r:I
tisa
ssu
medt
hen
atu
reo
fli
ghtc
ons
ide
reda
ndwee
xpl
ai
nva
rio
usp
hen
ome
nal
ik
e
r
efl
ect
ion
,re
fra
cti
on,i
nte
rfe
ren
ce,d
iff
rac
ti
ona
ndp
ola
riz
ati
ono
fli
ghte
tc.
,bya
ssu
min
gli
ght
a
sawa
vef
orm.
4.
Wha
tisi
nte
rfe
ren
ce?
An
swe
r:Th
efo
rma
tio
nofb
rig
hta
ndd
arkf
rin
geso
nsu
per
imp
osi
ngt
woc
ohe
ren
tli
ghtwa
vesi
s
c
all
edi
nte
rfe
ren
ce

5.
Wha
tar
eth
eco
ndi
ti
onsf
orc
ons
tru
cti
vea
ndd
est
ruc
tiv
ein
ter
fer
enc
e?

An
swe
r:Th
eco
ndi
ti
onf
orc
ons
tru
cti
vei
nte
rfe
ren
cet
ooc
curi
s

Pa
thd
iff
ere
nce= o
rph
ased
iff
ere
nce=2
.
Th
eco
ndi
ti
onf
ord
est
ruc
ti
vei
nte
rfe
ren
cet
ooc
curi
s

Pa
thd
iff
ere
nce= o
rph
ased
iff
ere
nce=

6.
Whe
nsu
nli
ghtf
all
sont
heo
ill
aye
rsa
nds
oapb
ubb
les
,di
ffe
ren
tco
lor
sar
epr
odu
ced
,wh
y?
An
swe
r:Wh
enas
unl
ig
htf
all
sont
hes
oapb
ubb
les
,af
il
mofo
ilf
loa
tin
gov
erawa
ter
,bu
tte
rfl
y
wi
ngsa
ndp
eac
ockf
eat
her
sdi
ffe
ren
tco
lor
sar
ese
en,t
hisi
sdu
etot
hei
nte
rfe
ren
ce(
res
ult
ing
f
romt
hel
ig
htb
etwe
ent
het
wos
urf
ace
soft
het
hinf
il
ms)i
nth
inf
il
msb
yre
fle
cti
ono
fli
ght
.


2

, Th
iswa
sfi
rs
tex
pla
ine
dbyTh
oma
syo
ungo
nth
eba
siso
fin
ter
fer
enc
e.




7.
Wha
tar
eth
eco
ndi
ti
onsf
orb
rig
hta
ndd
arkf
rin
gesi
npl
anepa
ral
el
lth
inf
il
m?

An
swe
r:Fo
rbr
igh
tba
nd: =(
2n+1
)

Fo
rda
rkb
and : =
8.
Wha
tar
eNe
wto
nri
ngs
?
An
swe
r:wh
enaPl
ano
-co
nve
xle
nswi
thi
tsc
onv
exs
urf
acei
spl
ace
donap
aleg
las
spl
ate
,th
ena
ir
f
il
misf
orme
dbe
twe
ent
hel
owe
rsu
rfa
ceo
fth
ePl
ano
-co
nve
xle
nsa
ndt
heu
ppe
rsu
rfa
ceo
fth
e
g
las
spl
ate
.Ifamo
noc
hro
mat
icl
ig
hti
sal
lo
wedt
ofa
lln
orma
ll
yont
hisa
irf
il
m,as
yst
emo
f
a
lte
rna
teb
rig
hta
ndd
arkc
ir
cul
arr
ing
sisf
orme
dint
hea
irf
il
m.Th
eser
ing
swe
red
isc
ove
redb
y
Ne
wto
nan
dar
eca
ll
edNe
wto
n’sr
ing
s.
9.
Wha
tist
hepr
inc
ipl
eofNe
wto
nri
ngs
?
An
swe
r:Ne
wto
n’sr
ing
sar
efo
rme
ddu
etoi
nte
rfe
ren
ceb
etwe
ent
hel
ig
htr
aysr
efl
ect
edf
romt
he
t
opa
ndb
ott
oms
urf
ace
sofa
irf
il
mbe
twe
ent
heg
las
spl
atea
ndt
hePl
ano
-co
nve
xle
ns.
1
0.Ce
ntr
als
poti
nNe
wto
n’sr
ing
spa
tte
rni
sal
way
sda
rk,wh
y?
An
swe
r:Att
hep
oin
tofc
ont
act‘
O’o
fth
ele
nsa
ndg
las
spl
ate
,th
eth
ick
nes
sofa
irf
il
mis
a
ppr
oxi
mat
elyi
sze
ro.i
.
e.
,t

Th
epa
thd
iff
ere
nce =2
t =2
(0)

=

Th
ust
het
wowa
vesa
rea
tth
ece
ntr
e,o
uto
fph
asea
ndi
nte
rfe
ren
ced
est
ruc
ti
vel
y.He
nce
t
hec
ent
rals
poti
sda
rk.
1
1.Wr
ites
omee
ngi
nee
rin
gappl
ic
ati
onso
fin
ter
fer
enc
e.
An
swe
r:Th
eph
eno
men
ono
fin
ter
fer
enc
eca
nbeu
sedi
nva
rio
use
ngi
nee
rin
gap
pli
cat
ion
s;s
ome
o
fth
eap
pli
cat
ion
sar
egi
venb
elo
w.
 I
tisu
sedi
nan
ti-
ref
lec
ti
ngc
oat
ing
s
 I
tisu
sedt
ode
ter
min
ati
ono
fth
ick
nes
sofat
hinf
il
mco
ati
ng
 I
tisu
sedi
nte
sti
ngo
ffl
atn
esso
fsu
rfa
ces
 I
tisu
sedi
nin
ter
fer
enc
efi
lt
erst
otr
ans
mitav
eryn
arr
owr
ang
eofwa
vel
eng
ths
.
13.
Dist
ing
uis
hbe
twe
enFr
aun
hof
er’
sdi
ffr
act
iona
ndFr
esn
eld
iff
rac
tio
n.
Answe
r:




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