1. No category

ｾＭＮ
ｉ＠
ISeries OSR I
55/3
Code No.
ＭｱｴＦｮｾ＠
<its
ｾｉ＠
q;) "3m:->'jffi!Chl ｾ＠
ｾＭ＠
Candidates must write the Code on the
title page of the answer-book.
ｾ＠
•
\lfT:q Cf>\ ｾ＠
• m-i:f?f -q ｾ＠
ｾｉ＠
ｾ＠
•
•
•
•
•
•
•
•
\lfT:q Cf>\ ｾ＠
ｾｃｦｩｬｻ［ｴＧ｀Ｂ＠
ｾ＠
ｾ＠
m-i:f?f -ij ｾ＠
m2r ｾ＠
ｾ＠
ｾ＠
3ffi
ｾ＠
ｾ＠
ｾ＠
m
m-i:f?f -ij aom ｾ＠
15 ｾ＠
ｾ＠
-·
1
em
ｾ＠
ｾＭｧｦｩＱｴ＠
ｾ＠
ｾＭ＠
1R
1
ｾ｣ｮｦｓｩｱＦ＠
I
＠ｾ
m-i:f?f em ｾ＠
ｾ＠ ｾ＠
15 ｾ＠
ｾ＠ ｾ＠
W:rr lT<fl ｾ＠ 1 m-i:f?f ｾ＠ fc«RuT ｾ＠
-ij 10.15 ｾ＠
ｾ＠
\ifTQ!IT I 10.15 ｾ＠
ｾ＠ 10.30 ｾ＠
ｾ＠
ｾ＠
ｾ＠
m-i:f?f ･ｭｾ＠
3fu ｾ＠ 31cffu ｾ＠ ｾ＠
ｾ＠ ｾＭｳｦｩＱ＠
'R ｾ＠
ｾ＠
ｾ＠
ｾ＠
1
Please check that this questio n paper contai ns 15 printe d pages.
Code numbe r given on the right hand side of the questi on paper should
be
writte n on the title page of the answe r-book by the candid ate.
Please check that this questio n paper contai ns 30 questio ns.
Pleas e write down the Serial Numb er of the quest ion befor
e
attem pting it.
15 minute s time has been allotte d to read this questi on paper. The questi
on
paper will be distrib uted at 10.15 a.m. From 10.15 a.m. to 10.30 a.m., the
studen ts will read the questi on paper only and will not write any answe r
on
the answe r-book during this period.
cqi ktcti ｾｉ＠
'"I ( ｾ＼［ｴｬｦＮ＿｡･ｩＩ＠
PHY SIC S (The ory)
ｾＳｦ｣ｮＺＷＰ＠
Time allowed : 3 hours
55/3
Maxim um Marks : 70
1
P.T.O.
www.examrace.com
ｾｷＮｲＡ＠
(i)
(ii)
I
ｾ＠
# jK7 80
JTR-TT;f
'f!C(; 3fcn r!fiT
ｾ＠
(iii)
( v)
>TR- r;;r ;f 81:m
w.r #
ｾ＠
ｾ＠
w;:ff 1{ ｾ＠
#
q,c1j)&c<
ｾ＠
c/; Wrr JrRr-&§Jrif/21 JTR t 3#f
JTR rft;r 3icn q;r
JtFN<cn >TR 9 I
w WI f¥tw4 :r!f # I rmrfrr, crT 3ien7 ｾ ﾷ＠ ｾ＠
w;:ff # 31Jrortfi.cn WlR ｾ＠
3hr rflFI Jien7 ｾＧｦｩｴＣ＠
1{, ?f/;r 3ien7
FcP:rr TTlTT ｾ＠ 1
JTR
JTR tt Cf>RT # I
ｾ＠
WI: TfTJ:"qZFf ., 8 ｾ＠
;rtf 9 1 rr2lTf2r ｾ＠ 31Jct:t21Cf? ｾ＠ rr7 3174' &!J'JuJc/i)JI
c/; '3T!ffl ctt ｾ＠
mruf t r!fiT ;rqfrr CR ｾ＠
(vii)
(fCf)
((1 3icn r!fiT 9, JTR 19 8 27 1{ ｾ＠
JTR rfhr 3fcn r!fiT # I
Jien7 CfTC? w;:ff # 8 ｾ＠
rfR
H8
9I
JTR
Wrr 9 tl18 1{ ｾ＠
9 3hr JTR 28 8 80 # ｾ＠
(ivJ
(vi)
JTR t I Wrr 1
317<#2/cn ｾ＠
t
I
3174' RA!&fisld ｾ＠
R21di(:;)J" c/; '11R1 r!fiT ｾ＠
CR ｾ＠
t:
8
c = 3 x 10 m/s
34
h = 6·63 x 10- Js
= 1·6 X 10-19 C
1
7
1-lo = 41t x 10- T mA-
e
1
- 4m; 0
ffie
= 9 X 109 N m 2 c-2
= 9·1 X 10-31 kg
Gen eral Inst ruct ions :
(i)
(ii)
(iii)
(iv)
5513
All ques tions are compulsory.
8 are very shor t answ er
There are 80 questions in total. Questions No. 1 to
type questions and carry one mar k each.
tions 19 to 27 carry
Questions No. 9 to 18 carry two mar ks each, ques
mar ks each.
thre e mar ks each and questions 28 to 80 carry five
htage is valu e base d
One of the questions carr ying three mar ks weig
question.
2
www.examrace.com
(v)
There is no overall choice. However, an interna l choice has been provide d
in one question of two marks, one question of three marks and all three
questions of five marks each weightage. You have to attemp t only one of
the choices in such questions.
Use of calculators is not permitted. However, you may use log tables if
necessary.
(vi)
(vii)
You may use the following values of physica l constants wherever
necessary:
c = 3 x 108 m/s
h
= 6·63 x lo-34 Js
e = 1·6 X 10-19 C
!lo = 4n x 10_7 .T mA-1
1
- -= 9
4nE 0
X 109
N m 2 c-2
me= 9·1 X 10-3 1 kg
m -ij ｾ＠
1.
./
ｾ＠
-ij ｾ＠
ｾ＠
'tOO ｾ＠
ｾ＠
ｾ＠
ｾ＠
ｾ＠
:mcJ ｾ＠
ＨｾＩ＠
ｾ＠
ｾ＠
ｾｬＨｱ＠
OR -ij ｓｬｱｾ＼Ｑ＠
ｾｉ＠
OR PQ ｾ＠
'tOO -ij ｾ＠
ｾ＠
ｾ＠
ｾ＠
ｾ＠
I
mWl
1
ｰＭｲｾｑ＠
0
A conduc ting loop is held below a current carryin g wire PQ as shown.
Predict the directio n of the induced current in the loop when the current
in the wire is constan tly increas ing.
ｰＭｾｲｑ＠
55/3
0
3
P.T.O.
www.examrace.com
2.
!f[1F
ｭｾ＠
-q ｾ＠ ｾＭ＠
mgm
f.rom fcMq v0 cnr ｾ＠
A ｾ＠
B ｾ＠
ｾ＠
ｾＧ＠
.-r.n ｾ＠
ｾ＠
1
ｾ＠
fc!Rf;{ol
<tl •
mgm -q -a ｾｭｧ＠
ｾ＠
v ｾ＠
ｾ＠
ｗｦｴﾷｾＳｵＺ｣ｭ＿＠
1
ｾｂ＠
'
W
- -0 /
e
'
./'
''
'
''
''
'
''
''
'
ｾａ＠
ｾ＠
fc!Rf;(UI
ｾﾷＨｶＩ＠
ｾ＠
The graph shows variation of stopping potential V0 versus frequency of
incident radiation v for two photosensitive metals A and B. Which of the
two metals has higher threshold frequency and why?
i
Metal B
Metal A
Stopping
potential
(Vo)
Frequency of incident
radiation (v) ｾ＠
- -e
55/3
4
..
www.examrace.com
[
ｾ＠
3.
ｾ＠
Gl ｾｒｩ･ｬＡ＠
ｾ＠
ｾｈ＠
'qleJCf>l ｾ＠
ｾ＠
ｾ＠
cfiT
fictif<'l"il Ｂ＼Ｚｦｩｔｾ＠
ｾｭｵ｣ｦｩｬ＠
1
Using the concept of force between two .infinitely long parallel current
carrying conductors, define one ampere of current.
1·25 ,3iqcHt"iiCfi ｾ＠
4.
ｾＭｩｪ＠
ｾ＠
Ｑｭｾ＠
ｾＲｦ＠
ｾ＠
I
-ij ?Cfiroll ｾ＠
-aR ｾ＠
ｾ＠
Ｈｦｬｾ＠
"3"1lllctctel ｾ＠
ｾＭｩｪ＠
cnl1·33 ＬＳｩｱ｣ｴｦｾｃｨ＠
Ol!CI$R
ｾ＠
Ｓｬｾ＠
ｾ＠
ｾ＠
I
1
A biconcave lens made of a transparent material of refractive index 1·25
is immersed in water of refractive index 1·33. Will the lens behave as a
converging or a diverging lens ? Give reason.
ｾＭ｡ｦ［ｲ＠
5.
＠ｾ
ｾＭ＠
cn1 ｾ＠ ｴｬｾ＠
?
Why do the electric field lines never cross each other ?
1
6.
1
To which part of the electromagnetic spectrum does a wave of frequency
5 x 1011 Hz belong?
7.
1
Why is it found experimentally difficult to detect neutrinos in nuclear
13-decay?
ｾﾷ＠
d.c. cilC'"tdl
ｃｦｩｲｯｬｾ＠
cfiT ｾ＠
-ij a.c. cilC'"tdl ｾ＠
ｾ＠
cn1 ｭｾｦｴｃｩ､ｬ＠
Cf<i1 ｾ＠ ｾ＠
ｾ＠
? C!)
I
1
Why is the use of a.c. voltage preferred over d.c. voltage ? Give two
reasons.
ｾ＠
9.
ｾ＠
ｾ＠
ｾＱＮＭｯ＼＠
ｾ＠
m
ｾ＠
ｾｭｲ･＠
ｾ＠
mu ｾ＠
CfiRUT '1G
Ol!"NCh ｾ＠
cfiT
Ｓｩｴｾ｣＠
ｾ＠
ｾ＠
cn1 ｾｦｩＺ＿ｬｒＱ｡＠
Ｓｩｬ｣ｴｾＡｃｦ､＠
ｾ＠
ｾ＠
ｾ＠
ｾ＠
ｾ＠
l:R
ｾ＠
ｾｬｲ＠
fcFm:
ｾ＠
ｾ＠ ｾ＠
Ｂｃｦｴｱｾ＠
ｾ＠
ｾ＠
CfiT
1
2
Considering the case of a parallel plate capacitor being charged, show
how one is required to generalize Ampere's circuital law to include the
term due to displacement current.
55/3
5
L
P.T.O.
r
www.examrace.com
ｾ＠
10.
ｾ＠
ｾ＠
em:,
ｾ＠
ｾＭ｣ｮｲＺ＠
Cfil ｾ＠
2·5 x 10-7 m 2 ＠ｾ ｾ＠
ｾ＠
2·7 A mu SIC41ftFi
"@ t, ｾ＠ ｾ＠
ｾｊｩ｣ｴ＿［ｔ＼Ｑ＠
cfiT ｾ＠
ｾ＠
ｾ＠
Cfil ｾ＠
ｾｉ＠
28
ｦ･ｮｾ＠
3
ｾＸｴ＿ｔ＼ｩＱ＠
Cfil ｾ＠
9x 10 m- ｾ＠ I
Esti mat e the ave rage drif t spee d of con duc
tion elec tron s in a cop per wire
of cros s-se ctio nal area 2·5 x 10- 7 m 2 carr
ying a curr ent of 2·7 A. Ass ume
the den sity of con duc tion elec tron s to be 9
x 1028 m-3 .
ｾ＠
11.
ｾ＠
ｾ＠
m
ｾＺ｣ｲ＠
ｾＨ･ｭｦＩ＠
'E' om 3'11'"(1f{Cf1 mu tr 'r' t, ｾ＠
ｾ＠
WlC1 ｾ＠
TTm ｾ＠ 1 ｾ＠
cfiT ｾ＠
c:ik·cjil 'V' 3fu: mu 'I'
1 ｾ Ｍ ｭ｣Ｚｐｃｦｩｬｾ＠
(emf) 3fu: ｾ＠
3'11'"(1ftcn >I'Rrittr CfiT ｾ＠
ｾ＠
>JCfiR
fuU B ｂｾｬ＠
>rRr{t'QCfl 'R' ｾ＠
ｾ｣ｮＩｭ［ｰ＠
ｦ･ｮｾ＠
2
Cfil ｾＭ＠
ｾ＠
ｾ＠
2
A cell of emf 'E' and inte rnal resi stan ce 'r'
is con nect ed acro ss a vari able
resi stor 'R'. Plot a grap h show ing vari atio
n of term inal volt age 'V' of the
cell vers us the curr ent 'I'. Usi ng the plot
, show how the emf of the cell
and its inte rnal resi stan ce can be dete rmi
ned .
mftn
12.
C ｾ＠
ｾ＠
ｾ＠
ｾ＠
'8ql'"(l( ｾ＠
m
ｾｴｮｦｵｬ＠
mfurr ｾ＠
ｾ＠
ｾｉ＠
col fcNq
ｾ＠
ｾｴｮｦｬＬ＠
ｾ＠
V CfCf1 ＳＧＱｾｃ＠
ＳＰＱｾ｡＠
ｾ＠
t, "B'
ｾ＠
3fu: ｾｭｦｵｃｩ＠
ｾＢｗ＼ｦ＠
TTm ｉ ｾ＠
B41WIC1 ｾ＠
I
2
A para llel plat e cap acit or of capa cita nce
Cis cha rged to a pote ntia l V. It
is then con nect ed to ano ther unc harg
ed cap acit or hav ing the sam e
capa cita nce. Fin d out the rati o of the
ene rgy stor ed in the com bine d
syst em to tha t stor ed init ially in the sing le
capa cito r.
ｾ＠
13.
ｾ＠
ｾ＠
&i ｻｾＨ｜｢ｬｩ＠
ｾ＠
ｾ＠
ｾ＠
ｾ＠
ｾ＠
ｾ＠
CfiT ｾ＠
ｾ＠
ｾ＠
ｾ＠
ｾｉ＠
ｾ＠
I ｾｊｬ｣ｴ＿ＨＢｩ＠
ｾ＠
ｾ＠
ｾ＠
ｾ＠
¥1 ｾ＠
Cfil ｾ＠
ｾ＠
ｾ＾ｊｃｦｬｒ｣ｩｲ｡＠
55/3
ＶＱｾ｜ｩｬＢ＠
ｾ＠
ｾＸ｣ｴ＿ｔ＼ｩ＠
::ttunc-qc:n ｾ＠
ｾｊｩ｣ｴ＿ｔ＼＠
cf;1 ｾ＠
ｾ＠
CfiT Cfm 312f ｾ＠
cf;1 neff cna11 ｾ＠
ｾ＠
?
2
ｾ＠
I
2
6
...
www.examrace.com
ｾ
l
L
Using Rutherford model of the atom, derive the expression for the total
energy of the electron in hydrogen atom. What is the significance of total
negative energy possessed by the electron?
OR
Using Bohr's postulates of the atomic model, derive the expression for
radius of nth electron orbit. Hence obtain the expression for Bohr's
radius.
(i) ｾｪＳｫｬ｣ｨ＼Ｚｴ＠
14.
ｾ＠
ｾ＠
Ｆｉｃｾｒ＠
ｾ＠
ｾ＠
(ii) ｓｬｫＳｩ］ｾ｣ｨ＼Ｚｴ＠
ｾ＠
@f::qq;{ ｾ＠
I ｾ＠
cfa ｾ＠
ｾ＠
if 3klchl<:t
ｾ＠
cfa
&13=11
ｾ＠
&11&41 ｾ＠
ｾ＠
cfit
ｾ＿＠
2
Show diagrammatically the behaviour of magnetic field lines in the
presence of (i) paramagnetic and (ii) diamagnetic substances. How does
one explain this distinguishing feature ?
3lfu9 cfa ｂｾｬ＼Ｚｴｯ＠
-qftq-2:[
15.
,.
ｾ＠
cfit
"B ｾ＠
&11&41 ｾ＠
p-n Bftr ｾ＠
ｾ＠
ＳｦＴＭｾ＠
Rt:>C:Chltl ｾｩｴ＠
I
2
Explain, with the help of a circuit diagram, the working of a p-n junction
diode as a half-wave rectifier.
16.
b
*
ｾ＠
ｷＧｬｦｵｾ＠
ｾ＠
("ll•ii:n'lul ｾａｂｃ＠
ｾ＠
ｾ＠
ｾＺ＠
ｾ＠
"
1·38
AB
3TitRR
3fu:
"Cfl«fi ｾ＠
1·52 ｾ＠
ｉｾ＠
'11{
ｾ＠
J1¥ffi
ｾｃｦｬｩｯ＠
ｾＴｃｩ､Ｂｦｬ＠
fen<oif
cn8 ｾ＠
I "fT fen<oif ｾｩｦ＠
ｾｉ＠
>rCnro
ｾ＠
cfa
'1' Cf '2'
ｾ＠
1:f2f
2
A
'1'
Ｍｾｴ＠
'2'-+----1
c
B
55/3
7
P.T.O.
...
www.examrace.com
Two mono chrom atic rays of light are incide nt norma lly on the face
AB of
an isosceles right- angle d prism ABC. The refrac tive indice s of the
glass
prism for the two rays '1' and '2' are respec tively 1·38 and 1·52. Trace
the
path of these rays after enteri ng throu gh the prism .
A
c
CE ｒｬｲ＼ｯｾ＠
17.
ｾ＠
-ij n-p-n
s;iMR< Ｍｳｲｱｾ＠
ｾ＠
ｾ＠
s;iMR< ｾ＠
Cl)T
Ｍｱｦｴｾ＠
3lfusr ｾ＠
ｉｾ＠
-ij ｾ＠
-ij CfiTcf CfiUfT ｾ＠ ?
2
Draw a circui t diagr am of n-p-n transi stor ampli fier in CE config
uratio n.
Unde r what condi tion does the transi stor act as an ampli fier ?
ｾ＠
18.
..
.q
ｾ＠
ｾ＠
CfiTcf ｾ＠
:
2
ｾ＠
(i)
!
ｦＮｩｱｾｵｬ､＠
Rlx:tT§eCfl
(ii)
Write the functions of the following in comm unicat ion system s :
(i)
Receiver
(ii)
Demo dulato r
20 em ｾ､ｭＱｱ［Ｉ＠
19.
ｾＦｔ＠
ｾＭ＠
20 ･ｭｾ＠
-6
15 em ｾ＠ lR &T TTm ＠ｾ I ｾ＠
fil"1fihd ｾ＠
ｾ＠ ｾ＠
$ ｾ＠
ｾ＠
"ffil-B 40 em ?tt lR &r \ifrnT 1ｾ＠ Ｔｬ｜Ｂｩ＠ｾ
ｾ＠
ｾ＠
ｓｉｒｴｦｩｬｾ＠
cf>t ｾ＠
mo
ｾ＠
I ｓｉｒｾ＠
Gf.HT ｾ＠
ｾ＠ ｾ＠
ｾ＠
3lfug ｾ＠
I
A convex lens of focal length 20 em is placed coaxially with a
convex
mirro r of radius of curva ture 20 em. The two are kept 15 em apart
.A
point object is placed 40 em in front of the convex lens. Find the
positi on
of the image formed by this combination. Draw the ray diagra m
showi ng
the image forma tion.
t
55/3
3
8
..
www.examrace.com
em ｾ＼Ｇ｜｣ｴ＿ｔＢｩ＠
20.
ｾ＼Ｇ｜｣ｴ＿ｬﾷｩ＠
ｾ＠
ｾ＠
ｾ＠
50 kV ｾ＠
-B ｾ＠
ｾＭ＠
en) m 1lr-ffi ｾＧ＠
､ｻｬｩｾＢｃＴ＠
ｓｉｃｦｩｾ＠
ｾ＠
cnC'"cdl ｾ＠
ｾ＠
ｾ＠
ｾ＠
ｾ＠
ｾ＠
ｾ＼Ｇ｜｣ｴ＿ｔＢｩ＠
ｾ＠
ｾ＼Ｇ｜ｩｦ＿ｔ［ｬ＠
I ｾ＠
ｾ＠
ｾ＠
cnr ｾ＠
ｾＧ＠
ｾ＠
ｾ＠
ｾ＠
ｾ＠
ｾ＠
Q)ar t, ｾ＠
CfiT ｾ＠
Cf>«<T
ｾ＠
ｾ＠
I
ｾ＠
ｾ＠
ｾ＠
t
ｾ＠
t
?
3
An electron microscope uses electrons accelerated by a voltage of 50 kV.
Determine the de-Broglie wavelength associated with the electrons.
Taking other factors, such as numerical aperture etc. to be same, how
does the resolving power of an electron microscope compare with that of
an optical microscope which uses yellow light ?
ｾ＠
3l100 ｾ＠
ｾ＠
31Ttm 1:R ilR1Chl, ｾ＠
3fu: ｾＭ＠
ｾ＠
iftq ｾｇＩ＠
ｾＨＱＢ｣ｮｬ＠
3
Write
any
two
distinguishing
features
between
conductors,
semiconductors and insulators on the basis of energy band diagrams.
ｾ＠
22.
ｾ＠
ｾ＠ ｾ＠
ｾ＠
ｾｗｉ＠
ＨｾＩ＠
I 3WnlT Ｔｔﾧｾ］Ｑ＠
3lit& cnt &l"ilcti\ ｾ＠
ｾ＠
ｾ＠
ｾ＠
ｾ＠
ＳＱｾｵｱｯＧ＠
ｾ＠
ｾ＠
ｾ＠
ｾ＠
fcf> ｾ＠
3l1<fllJ 4T§Wtd
)I"Cf)'R
ｾ＠
ｾ＠
\i"41qshlll ｾ＠
Olll@l ｾ＠
I
Wl1 1R Ｔｔﾧｾ｣ｮ＠
fur.:R.1 >Trn ｾ＠
ｾ＠
t
1
3
Write two basic modes of communication. Explain the process of
amplitude modulation. Draw a schematic sketch showing how amplitude
modulated signal is obtained by superposing a modulating signal over a
sinusoidal carrier wave.
3
(a)
lfR:< "Bg -ij
\ifRfT
(b)
Ｂｓｦｩｲｯｾ＠
ｾ＠
cnT cnftR
iftq ｾｴｩｨＮｦ＠
ｾ＠
llltt t® CfiT ｾ＠
ｾ＠
t?
lfR:\ ｾ＠
ｾ＠
<m: l:R ｾＱＴＢｬ､Ｚ＠
ｾ･ｮＩ＠
lf'al -ij >Trn ｾ･ｮＩ＠
Ｂｓｊｔｾｦ＿Ａｃｬ､＠
ｾｴ＿＠
(c)
lfR:< "Bg ｾ＠ <m: ｾ＠ ｾ＠
ｾ＠
55/3
ｾ＠
CfiT ｾ＠
9
ｾ＠
\ifRfT
t 3fu: ｾ＿＠
P.T.O.
...
www.examrace.com
L _
ｾ＠
ｾ＠
ｾ＠
-ij ｾ＠
3Wffi
>rfuUcq
Ro Q ｾ＠
ｾ＠
RQ
OR ｾ＠
ｾｉ＠
ｾ＠
>TfWrcq ｾ＠
ｾ＠ 't.lRT 'ffirr ｾ＠ I ｾ＠
I ｾ＠
col V Jl<'"cdl cfa ｾ＠
cfa \ifRft ｾ＠
li'G f -ij t ｾ＠
R ｾ＠ fuU -en: Jl<'"cdl ｾ＠
ffi"Q: ｾ＠
Cf)T
.- -- -- -- V - - - - -
-,
,w,,
'j
An sw er th e following
Cf)T
I ｾ＠
ｾ＠
ｾ＠
ｾＬ＠
:
(a)
W hy ar e th e co nn ec tio
ns be tw ee n th e re sis to
rs in a m et er br id ge
m ad e of th ick co pp er str
ip s ?
(b)
W hy is it ge ne ra lly pr
ef er re d to ob ta in th e
ba la nc e po in t in th e
mi dd le of th e m et er br
id ge wi re ?
(c)
W hi ch m at er ia l is us ed
for th e m et er br id ge wi
re an d w hy ?
OR
A re sis ta nc e of R Q dr
aw s cu rre nt fro m a po
te nt io m et er as sh ow n
in th e
figure. Th e po te nt io m
et er ha s a to ta l re sis
ta nc e R0 Q. A vo lta ge
V is
su pp lie d to th e po ten tio
me ter . De riv e an ex pr es
sio n fo r th e vo lta ge ac ro
ss
R wh en th e sli di ng co nt
ac t is in th e mi dd le of th
e po te nt io m et er.
.- -- -- -- V - - - - -,
ｾ
55/3
10
ﾷ＠
www.examrace.com
3
ｾ＠
24.
¥9 ｾ＠
3fu: fShlf ｉｃｦｩｾ＠
ｾｉｃｦｩ＠
Ill (1
ｾ＠
-B 3lmfT 31CRT ｾ＠ um cf?t ¥9 ｾ＠
141 .q (O!J<I;:qlf .q "Cfilft CfiT ｾ＠
Cfil: ｾ＠
2ft
m"Cfi«ft 2ft
item ;r um
1
I
3lmfT ｾ＠ ｾ＠
CfiT ｾ＠
liTffi -ftrnl ｾ＠
Ｍ｣ｲｴｾ＠
ｾ＠
ｾ＠
ｾ＠
ｾ＠
ｾｉ＠
3Wffi 311Uft ;r fcf;;{ ｾ＠
(a)
ｾ＠
(b)
mm3ii$B1 il4 ｾ＠
)ICf)R
I ｾ＠
ct?t ｾＭ＠
ｾ＠
ｾ＠
cf& ｾ＠
Ｍｾ＠
um cfiT ifcfc:tTＭｾ＠
ｾ＠
fcfi um ｾＭ＠
M
cnT ｾ＠
ｾ＠
:tllt1f):Cfi ｾＧ＠
cfiT
CfiT
mrrcr
-B
?
CfiT ｾ＠
.q ('!Qilfdl ｾ＠
m
ｾ＿＠
3
For the past some time, Aarti had been observing some erratic body
movement , unsteadin ess and lack of coordinati on in the activities of her
sister Radha, who also used to complain of severe headache occasionally.
Aarti suggested to her parents to get a medical check-up of Radha. The
doctor thoroughl y examined Radha and diagnosed that she has a brain
tumour.
25.
What, according to you, are the values displayed by Aarti?
(b)
How can radioisoto pes help a doctor to diagnose brain tumour?
(a)
z ｾ＠
cf?t ｾ＠
ｾ＠
Q!-fl(O!J<IH ｾｫｬ｣ｦＩ＠
ｾ＠
!$r .q
ｾ＠
ｾ＠
Q!-fl('!J<IH ｾ＠
ｾｦｵ､ｇｩＺｱｭＮ［Ｈ･Ｉ＠
ｾ＠
(b)
ｦ｣ｲｷｬＭｾ＠
(a)
'\
(b)
55/3
\
(a)
ｾ＠
'v'
"B
C1kl*l ｾｭ＠
ｾＺ＠
ｾ＠
ｾ＠
ｾ＠
ｾＨ･ｭｦＩ＠
ｾ＠
ｾ＠
"tR ｾ＠
cnT ｾ＠
ｾ＠
1'fffi ｾ＠
ｾ＠
\ifRft t
I ｾ＠
1
Mft"{'#t ＠ｾ
Cf)T ＠ｾ
ｾ＠
lB' ｾ＠
)ICf)R ＠ｾ
ｾ＠ -aCfiffi ｾ＠ ? Olfi&QI ｾ＠
I
3
A rod of length l is moved horizontal ly with a uniform velocity 'v' in
a direction perpendic ular to its length through a region in which a
uniform magnetic field is acting vertically downward . Derive the
expression for the emf induced across the ends of the rod.
How does one understan d this motional emf by invoking the
Lorentz force acting on the free charge carriers of the conductor ?
Explain.
11
P.T.O.
www.examrace.com
26.
ｾ＠
(a)
3lTt&
ｾ＠
ｾ＠
ｾ＠
(b)
ｾＧ＠
GJQ ｾ＠
P 1 Ｈｦｾ＠
<1Mi!Cl<i_
ｾ＠
t
fenGfT \jfT ｾ＠
ＴＩｊｬ､ｾｳ＠
ｾ＠
ｾ＠
4{1Cld"i ｾ＠
I
P 2 ｣ｩｴｾ＠
mI ｾ＠
&P T( iT
10 q:;r ｾ＠
t ｾ＠
ＳＱｾ＠
ｾ＠
ｾ＠
cit ｾ＠
l:ffftcr-31a:r ｾＭ＠
ｾ＠
P 1 'tl'{ ｾ＠
I fcnBT cfR:R
P3 CfiT P 3fu: P ｾ＠
＠
ｾ
＠
ｾ
1
)fC f)R "{@ 'l'1m
2
fcn ｾ＠
"tJTfuf-31a:r P 1 ｾ＠ "4'Tftf-31a:r ｾ＠ 60° q:;r
CfiTur ｾ＠
I P 1' P 3fu: P ｾ＠ ｾ＠
2
3
ｾ｣ｲ［＠
I
Sh ow , giv ing a su ita ble
dia gr am , ho w un po lar ize
d lig ht ca n be
po lar ise d by ref lec tio n.
ＴＱｊｬＶｾｳ＠
(a)
(b)
t
t
3
Two po lar oid s P an d
P 2 are pla ce d wi th the
1
ir pa ss ax es
pe rp en dic ula r to ea ch oth
er. Un po lar ise d lig ht of
int en sit y 1 is
inc ide nt on P . A th ird po
0
lar oid P is ke pt in be tw
1
ee n P an d P
3
su ch th at its pa ss ax is
1
2
ma ke s an an gle of 60°
wi th th at of p 1"
De ter mi ne th e int en sit y
of lig ht tra ns mi tte d thr ou
gh P 1' P an d
2
P3
.
ｾ＠
27 .
ｾ＠
ｾＭｱ＠
ｾ＠
LC R ＢｙｦｵＺｊｾ＠
ｾ＠
'tl'{
ｾ＠
ｾｉｃＢ｣ｯ､ｬ＠
V
｡｟ｗｲｮｾ＠
ｾ＠
-q
m<rr, (ii) ＢｙｦｵＺｊｾ＠
= V0
sin cot ｾｪｓｉＱＧｦｩ＠
t
cr;r ｾ＠
I ｾ＠
I
(i) ｾ＠
ＭｱｦｵＺｊｾ＠
-q ｾ＠
= V0
-q ｾ＠
ｭＭｾ＠
mu
m<rr t
m '4T ｾＭ＠
SICIIf%d ｾｗｉｴ＠
?
ｾ＠
3
A vo lta ge V
sin cot is ap pli ed to a se
rie s LC R cir cu it. De riv e
ex pre ssi on for the av era ge
the
po we r dis sip ate d ov er a cy
cle.
Un de r wh at co nd iti on is
(i) no po we r dis sip ate d ev
en tho ug h the cu rre nt
flows thr ou gh the cir cu
it, (ii) ma xim um po we
r dis sip ate d in the
cir cu it?
28 .
W1 ｾ＠
＠ｾ
:qq4))ct)
(a)
ｾＢｓｉｔｈ＠
<rr ｾ＠
(b)
ｾ＠
ｾ＠
ｾ＠
3fu: ｾ＠
m
m
c(;T ｾＴＱ＠
-q,
ｾ＠
mft<:rT
ＨｾＩ＠
-q CfOT;r ｾ＠
ｾ＠
ｾ＠
ｾ＠
"5liH cr;r ｾ＠
ｾ＠
I
-q PtrAGO 3fu: ｾ＠
q:;r 31jtfRf "ffiO ｾ＠
ＳＱｾ＠
55 /3
ｾ＠
c(;T
cfurnr311 Cf)T ｾ＠
I
ｾ＠
ｾ＠
ｾ＠
I ｾ＠
ｾ＠
ｾ＠
'tl'{
ｾ＠
9 : 2s ｾ＠
1
5
12
www.examrace.com
(a)
-q quf;r ｾ＠
fWT ｾ＠ ｾ＠
ｾ＠
ｾ＠
ｾ＠
)l'Tt(f
ｾ＠
ｾ＠
ｾｃｦＩｱｏ｛＠
11\
3fu:
ｾ＠
fuc«R
ｦｾ＼ＩＨＡ･ｰ＠
ｾ＠
ｾ＠
ｾ＠
ｾ＠
ｾ＠
ｾ＠
>rrn M
)ICf)R
Ptfi:it56 ｾ＠
ｾ＠
ｾ＠
ｾ＠
\jffifT
ｾ＠
ｾ＠
ｾ＠
I
ｾ＠
ｾｉ＠
Ｖ
2 x ＱＰＭ
(b)
ｾ＠
ｾ､ｬ＼ｏＡｃｦ＠
)J(fi"R
fenm
ｾ＠
fWT ｾ＠
ｭｾ＠
ｾＭｩｦ＠
ｦｴｬｾ＼ｏｉａ＠
M
>rrn m-eR ｾ＠
cnT ｾ＠
ｾ＠
ｾ＠
I fWT
T[(f[
-q
ｾ＠
3fu: ｾ＠
ｾ＠
ｾ＠
ｾ＠
ｾ＠
3Gi:lt56 ｾ＠
ｾ＠
ｾ＠
nm ｾ＠
3fu: 596
590 run
ｾ＠
cnT 3l'l::<l<R ｾ＠
ｾ＠
1·5 m ｾ＠
Ｑ＿ｾ＠
ｾ＠
ｾ＠
Ｑ
､ｻ
I ｾ＠
ｾ＠
ｾ＠
ＱｾＧｕｉ＠
-q
ｾ＠
ｾ＠
qft6flred
ｾｉ＠
(a)
5
(b)
In Young's double slit experiment, describe briefly how bright and
dark fringes are obtained on the screen kept in front of a double
slit. Hence obtain the expression for the fringe width.
The ratio of the intensities at minima to the maxima in the
Young's double slit experiment is 9 : 25. Find the ratio of the
widths of the two slits.
( )
\..\
OR
29.
(a)
Describe briefly how a diffraction pattern is obtained on a screen
due to a single narrow slit illuminated by a monochromatic source
of light. Hence obtain the conditions for the angular width of
secondary maxima and secondary minima.
(b)
Two wavelengths of sodium light of 590 nm and 596 nm are used
in turn to study the diffraction taking place at a single slit of
aperture 2 x 10- 6 m. The distance between the slit and the screen
is 1·5 m. Calculate the separation between the positions of first
maxima of the diffraction pattern obtained in the two cases.
(a)
1At4i1<01
ｾ＠
ｾ＠
-q M
ＳＧＱｾ､＠
3fu: ｾ＠
ｾ＠
ｾ＠ ｾ＠
onur ｾ＠
•
qftSfiAOI ｾ＠
q;ur ｾ＠
ｾ＠
Wr
ｾ＠
ｾ＠
ｾ＠
-en:
;w.rcn ｾ＠
ｾ＠
-Rm:
ｾｉ＠
ｾｃｋＱＧｬ＿ｔＢ＠
(b)
ｾ＠
CfiT ｾ＠
ｾ＠
ｾ＠
ｾ＠
ｾ＠
ｾ＠
"§:Q: 041&11 ｾ＠
)ICf)R
M
f<n
\jffifT
I ｾ＠
ＳＧＱｾＨ＠
6I
ｾ＠
q;uft -Ch)
cnT 3'11ct!i4i:.h ｾ＠
rctitJ ｾ＠
ｾ＠
ｾ＠
ｾ＠
5
Ｓｴｾ＠
55/3
"
13
P.T.O .
...
www.examrace.com
T.R1 ｾｯＺｧｈｊ＠
(a)
ｾ＼Ｂ＿ｐｦｬ｣ｘ＠
Cht<fst on cll CfiT
CfiT •llliiRtla ｾ＠
R&:;1R1fula ｾ＠
(b)
ｾ＠
ｾ＠
ｾ＼ＢﾷｴｨＺｦｬ｣＠
(i)
ｾ＠
ｾ＠
I ｾ＠
3fu:
ru;&t'fl
I
ｾｯＺｧ｣ｩＩ＠
ｾ＠ ＱｃｬｾＴｨ＠
"Rtlm
(ii)
croR ｾ＠
:
-aa)-cr ｾ＠
ｾ＠
ｾ＠
ｾ＠
efRJ ;flf
ｾ＠
9n1:s en)
ｾｈｉｃｨｬＨ＠
ｾ＠
ｾ＠ ?
ｾＢＱＴ｣ｸ＠
cfiT mu ｾｷｒ［｡ｴ＠
fcf; ｾ＠
ql<"cdl ｾＱＥＨ＠
ｾＰＴＱ｀＠
-q
ｾ＠
ｾ＠
ｾ･ｮＭｇ＠
CfiT ｾ＠
ｾｒｃｬＴ､Ｚ＠
mｾ＠
ｾ＠
ｾ＠
ｾ＠
I
"Cf)RUT
ｾ＠
I
5
(a)
Deduce an express ion for the frequency of revolut ion of a charged
particle in a magnet ic field and show that it is indepen dent of
velocity or energy of the particle .
(b)
Draw a schema tic sketch of a cyclotron. Explain, giving the
essenti al details of its constru ction, how it is used to acceler ate the
charged particle s.
ｾ＠
J.-1'
OR
(a)
Draw a labelled diagram of a moving coil galvano meter. Describ e
briefly its princip le and working.
(b)
Answer the following :
(i)
Why is it necessa ry to introdu ce a cylindr ical soft iron core
inside the coil of a galvano meter ?
(ii)
Increas ing the current sensitiv ity of a galvano meter may not
necessa rily increas e its voltage sensitiv ity. Explain, giving
reason.
ｾ＠
30.
ｾ＠
ｾ＠
ｾ＠
ｾ＠
ｾ＠
ｾ＠
ｾ＠
ｾ＠
'ChT "llliiFtla ｾ＠
ｾ＠
ｾｬＢＧｦｻ｡＠
ｾｬ､＠
ｾ＠
ｾ＠
I ｾ＠
｜ｩｬｾ＠
ｾ＠
ｾ＠
t
ｾ＠
ｾ＠
ｔｦｬｈｾＧｃｨｯＲ＠
ｾ＠
ｾ＠
ｾ＠
ｾ＠
ｾ＠
ｾ＠
fcfi,
ｾ＠
ｾ＠
"tR ｾ＠
"Rtlm
'SICfm:
l1ffi -ij
Cf1T Chi4Cfil{) m;&l'fl ｾ＠
1 ｾ＠
1
(a)
ｾ＠
QlheliH
ｾＭｬＤｊ＠
E cfiT ｾ＠
ｾ＠ ｾ＠
"tR ｾ･ｮｇＭ＠
55/3
ｾ＠
ｾ＠
5
t crra ｾ＠
ｾ＠
I
14
...
www.examrace.com
sl o2IT s2 ｾｭＭｮＺ＠
ｭＭｩｪｾ＠
(b)
ｾ＠
2Q (l2IT 4Q ｾ＠
1Cii) ｾ＠
3WTif ｾ＠ ｾ＠
m: ｾ＠
'er' Cf)l ｾ＠ ｾ＠
? ｩｬ｣ｴｾＴ＠Ｓ
qf):c:nf"l
ｾ＠
mrn
I (i) ｾ＠
\fuRt ｾ＠
s1
ｾ＠
ｾ＠
ｾ＠
ｾＺ＠
s1 ｾ＠
ｾＬ＠
m
ｾ＠
ｾ＠
ｾ＠
ｾ＠
ｾ＠
-ij ｾ＠
ｾ＠
-B ｾ＠
ｾ＠
"CffiCm cnT
tn: Ｔ＼Ｑｾ｡ｩ＠
＠ｾ
＠ｾ
qffi ｾ＠
-q
5
I
·'
/
Draw a labelled diagram of Van de Graaff generator. State its working
principle to show how by introducin g a small charged sphere into a larger
sphere, a large amount of charge can be transferre d to the outer sphere.
State the use of this machine and also point out its limitation s.
OR
(a)
Deduce the expression for the torque acting on a dipole of dipole
moment
(b)
55/3
p in the presence of a uniform electric field "Ef .
Consider two hollow concentric spheres, S1 and S2, enclosing
charges 2Q and 4Q respectively as shown in the figure. (i) Find out
the ratio of the electric flux through them. (ii) How will the electric
flux through the sphere sl change if a medium of dielectric
constant 'Er' is introduced in the space inside S1 in place of air ?
Deduce the necessary expression.
4Q
15
www.examrace.com