HBSE Class 12 Physics Question Paper 2018 Set B

CLASS : 12th (Sr. Secondary) Code No. 3628
Series : SS-M/2018

Roll No. SET : B
HkkSfrd foKku
PHYSICS
[ Hindi and English Medium ]
ACADEMIC/OPEN
(Only for Fresh/Re-appear Candidates)

Time allowed : 3 hours ] [ Maximum Marks : 60
• Ñi;k tk¡p dj ysa fd bl iz'u&i= esa eqfnzr iz'u 18 gSaA
Please make sure that the printed question paper are contains 18
questions.
• iz'u&i= esa nkfgus gkFk dh vksj fn;s x;s dksM uEcj rFkk lsV dks Nk= mÙkj&iqfLrdk ds
eq[;&i`"B ij fy[ksaA
The Code No. and Set on the right side of the question paper should be
written by the candidate on the front page of the answer-book.
• Ñi;k iz'u dk mÙkj fy[kuk 'kq: djus ls igys] iz'u dk Øekad vo'; fy[ksaA
Before beginning to answer a question, its Serial Number must be written.
• mÙkj&iqfLrdk ds chp esa [kkyh iUuk@iUus u NksMsa+A
Don’t leave blank page/pages in your answer-book.
• mÙkj&iqfLrdk ds vfrfjDr dksbZ vU; 'khV ugha feysxhA vr% vko';drkuqlkj gh fy[ksa vkSj fy[kk
mÙkj u dkVsaA
Except answer-book, no extra sheet will be given. Write to the point and do
not strike the written answer.
• ijh{kkFkhZ viuk jksy ua0 iz'u&i= ij vo'; fy[ksaA
Candidates must write their Roll Number on the question paper.
• d`i;k iz'uksa dk mÙkj nsus lss iwoZ ;g lqfuf'pr dj ysa fd iz'u&i= iw.kZ o lgh gS] ijh{kk ds
mijkUr bl lEcU/k esa dksbZ Hkh nkok Lohdkj ugha fd;k tk;sxkA
3628/(Set : B) P. T. O.

(2) 3628/(Set : B)
• Before answering the questions, ensure that you have been supplied the
correct and complete question paper, no claim in this regard, will be
entertained after examination.

lkekU; funsZ'k %
(i) ç'u-i= esa dqy 18 ç'u gSAa
(ii) lHkh ç'u vfuok;Z gSAa
(iii) ç'u la[;k 1 esa 1-1 vadksa ds ckjg (i-xii) cgqfodYih; ç'u gSAa çR;sd ç'u ds pkj laHkkfor
mÙkj gSA vkidks blesa ls loksZÙke mÙkj pquuk gS vkSj ml mÙkj dks viuh mÙkj&iqfLrdk esa
fy[kuk gSA
(iv) ç'u la[;k 2 ls 10 rd vfry?kq mÙkjh; ç'u gSa rFkk çR;sd ç'u 2 vadksa dk gSA
(v) ç'u la[;k 11 ls 15 rd y?kq mÙkjh; ç'u gSa rFkk çR;sd ç'u 3 vadksa dk gSA

(vi) ç'u la[;k 16 ls 18 rd nh?kZ mÙkjh; ç'u gSa rFkk çR;sd ç'u 5 vadksa dk gSA
(vii) ç'u-i= esa lexz :i ls dksbZ fodYi ugha gSA rFkkfi 5 vadksa okys rhuksa ç'uksa esa vkUrfjd
p;u çnku fd;k x;k gSA ,sls ç'uksa esa ls vkidks fn, x, p;u esa ls dsoy ,d gh ç'u
djuk gSA
(viii)dSYD;qysVj ds mi;ksx dh vuqefr ugha gSA vko';d gksus ij] y?kqx.kdh; lkjf.k;ksa dk ç;ksx
fd;k tk ldrk gSA
(ix) tgk¡ vko';d gks vki fuEufyf[kr HkkSfrd fu;rkadksa ds ekuksa dk mi;ksx dj ldrs gSa %
c = 3 × 10 8 m/s µ 0 = 4π × 10 −7 Tm A −1
1
h = 6.63 × 10 −34 JS = 9 × 10 9 Nm2C − 2
4π ∈0
e = 1.6 × 10 −19 C me = 9.1 × 10 −31 kg
General Instructions :
(i) There are 18 questions in all.
(ii) All questions are compulsory.
(iii) Question number 1 consists of twelve (i-xii) multiple choice type
questions each of 1 mark. Each question has four possible answers.

3628/(Set : B)

(3) 3628/(Set : B)
You have to select best answers out of these and write in your
answer-sheet.
(iv) Question Numbers 2 to 10 are very short answer type questions and
carry 2 marks each.
(v) Question Numbers 11 to 15 are short answer type questions and
carry 3 marks each.
(vi) Question Numbers 16 to 18 are long answer type questions and
carry 5 marks each.
(vii) There is no overall choice. However, an internal choice has been
provided in all three questions of 5 marks each. You have to attempt
only one of the given choice in such questions.
(viii)Use of Calculators is not permitted, if required you may use
logarithmic tables.
(ix) You may use the following values of physical constants whenever
necessary :
c = 3 × 10 8 m/s µ 0 = 4π × 10 −7 Tm A −1
1
h = 6.63 × 10 −34 JS = 9 × 10 9 Nm2C − 2
4π ∈0
e = 1.6 × 10 −19 C me = 9.1 × 10 −31 kg

[ cgqfodYih; iz'u ]
[ Multiple Choice Type Questions ]

1. (i) fuEufyf[kr esa ls dkSu oS|qr~-pqacdh; rjaxsa gSa \ 1

(A) /ofu rjaxsa (B) α-fdj.ksa
(C) β-fdj.ksa (D) γ-fdj.ksa
Which of the following are electromagnetic waves ?
(A) Sound waves (B) α-rays

(C) β-rays (D) γ-rays

3628/(Set : B) P. T. O.

(4) 3628/(Set : B)
(ii) +4D {kerk ds ysal dh Qksdl nwjh gS % 1
(A) − 25 lseh (B) + 25 lseh
(C) − 4 lseh (D) + 4 lseh
The focal length of a lens of power +4D is :
(A) − 25 cm (B) + 25 cm
(C) − 4 cm (D) + 4 cm
(iii) dkSu-lk çHkko çdk'k rjaxksa dh d.kh; çÑfr dks n'kkZrk gS \
1
(A) O;frdj.k (B) foorZu
(C) /kzqohdj.k (D) buesa ls dksbZ ugha
Which phenomenon illustrates particle nature of light waves ?
(A) Interference (B) Diffraction
(C) Polarization (D) None of the above

(iv) ,d Vh0 oh0 Vkoj dh Å¡pkbZ 32 ehVj gSA ;fn i`Foh dh f=T;k 6400 fdeh gks] rks
bldk çlkj.k vf/kdre fdruh nwjh rd fd;k tk ldrk gS \ 1
(A) 6.4 10 fdeh (B) 64 10 fdeh
(C) 64 fdeh (D) 640 fdeh
The height of a T. V. tower is 32 m. If radius of earth is 6400 km,
then what is the maximum distance of transmission from it ?
(A) 6.4 10 km (B) 64 10 km
(C) 64 km (D) 640 km

(v) 100 V ds foHkokUrj }kjk Rofjr fdlh bysDVªkWu ls lacaf/kr ns czkWXyh rjaxnS?;Z gS % 1

(A) 12.70 nm (B) 5.227 nm

(C) 1.227 nm (D) 0.123 nm

The de Broglie wavelength associated with an electron accelerated
through a potential difference of 100 V is :

3628/(Set : B)

(5) 3628/(Set : B)
(A) 12.70 nm (B) 5.227 nm
(C) 1.227 nm (D) 0.123 nm
(vi) gkbMªkstu ijek.kq ds LisDVªe esa dkSu-lh Js.kh ijkcSaxuh {ks= esa gksrh gS \ 1
(A) ykbeSu (B) ik'ku
(C) QqaV (D) ckej
Which spectral series of hydrogen atom lie in the ultraviolet region ?
(A) Lyman (B) Paschen
(C) Pfund (D) Balmer
(vii) ,d çksVkWu ij vkos'k gksrk gS % 1
(A) 0 C (B) 1C
(C) − 2.6 × 10 +19 C (D) + 1.6 × 10 −19 C
The charge on an Proton is :
(A) 0 C (B) 1C
(C) − 2.6 × 10 +19 C (D) + 1.6 × 10 −19 C

(viii)nks vkosf'kr d.kksa ds chp dh nwjh vk/kh djus ij muds chp cy gks tkrk gS % 1

(A) ,d-pkSFkkbZ (B) vk/kk

(C) nksxquk (D) pkj xquk

When the distance between two charged particles is halved, the
force between them becomes :

(A) one-fourth (B) half
(C) double (D) four times

(ix) rkieku esa deh ls fdlh pkyd dh çfrjks/kdrk % 1

(A) c<+ tkrh gS

3628/(Set : B) P. T. O.

(6) 3628/(Set : B)
(B) ?kV tkrh gS

(C) dHkh c<+ tkrh gS dHkh ?kV tkrh gS

(D) dksbZ cnyko ugha gksrk

With decrease in temperature, the resistivity of a conductor :

(A) increases

(B) decreases

(C) may increases or decreases

(D) does not change

(x) 5 kΩ ds çfrjks/kd ds fljksa ij 5V foHkokUrj yxk gks] rks blesa fdruh fo|qr~ /kkjk cg
jgh gS \ 1

(A) 1 µA (B) 1 mA

(C) 1 A (D) 5 A

How much current is flowing through a 5 kΩ resistor when a
potential difference of 5V is applied across its ends ?

(A) 1 µA (B) 1 mA

(C) 1 A (D) 5 A

(xi) fdlh fo'kq) /kkfjrk ifjiFk ds fy, 'kfDr xq.kkad dk eku gksrk gS % 1

(A) 1 (B) 0

(C) 2 (D) 2
The value of power factor for a purily capacitive circuit is :

(A) 1 (B) 0

(C) 2 (D) 2

3628/(Set : B)

(7) 3628/(Set : B)
(xii)fdlh ifjiFk esa çR;korhZ /kkjk i = I 0 sin(ωt − π / 2) çokfgr gks jgh gSA bl /kkjk dk
r.m.s. eku gS % 1
(A) I 0 (B) I 0 / ω

(C) I 0 / 2 (D) ωI 0

An alternating current i = I 0 sin(ωt − π / 2) is flowing in a circuit.
The r.m.s. value of this current is :

(A) I 0 (B) I 0 / ω

(C) I 0 / 2 (D) ωI 0

[ vfry?kq
vfry?kq mÙkjh; ç'u ]
[ Very Short Answer Type Questions ]

2. fuEukafdr fp= esa nks fcUnqvksa A vkSj B ds chp dh /kkfjrk Kkr dhft, %
2

C1 C2 C3 C4
A P Q R
B
5 µF 2 µF 3 µF 10 µF

Calculate the equivalent capacitance between the points A and B in the
following Figure :

C1 C2 C3 C4
A P Q R
B
5 µF 2 µF 3 µF 10 µF

3. fdj[kksQ ds ywi ¼ik'k½ fu;e dks le>kb,A 2

3628/(Set : B) P. T. O.

(8) 3628/(Set : B)
Explain the Kirchhoff's loop rule.

4. foHkoekih ds dk;Z fl)kUr dks ifjiFk fp= dh lgk;rk ls le>kb,A
2
State the principle of working of a potentiometer using a circuit
diagram.

5. pqacdh; ço`fÙk χ ds in dks ifjHkkf"kr dhft, vkSj bldk ek=d fyf[k,A
2
Define the term magnetic susceptibility χ and write its unit.

6. vU;ksU; çsjdRo D;k gS \ le>kb,A 2
What is mutual inductance ? Explain.

7. fdlh lery oS|qr~ pqacdh; rjax esa fo|qr~ {ks= %
Ex = 5.1 cos( 1.8 × 10 −2 y − 5.4 × 10 6 t ) U;wVu/dwykWe gSA bl rjax dh vko`fÙk rFkk rjaxnS?;Z
D;k gS \ 2
The electric field in a plane electromagnetic wave is :
Ex = 5.1 cos( 1.8 × 10 −2 y − 5.4 × 10 6 t ) Newton/Coulomb. What is the
wavelength and frequency of this wave ?

8. jnjQksMZ ds ,sYQk d.k çdh.kZu ç;ksx esa ,sYQk d.k dh xfrt ÅtkZ rFkk bldh ukfHkd ls
lehire nwjh esa laca/k fyf[k,A 2
Write the relation between kinetic energy of α-particle and its
distance of closest approach from nucleus in Rutherford's α-scattering
experiment.
9. fuEukafdr fp= esa fn[kk, x, ifjiFk ds fy, lR;eku lkj.kh cukb,A ;g ifjiFk fdl xsV dh
Hkk¡fr O;ogkj djrk gS \ 2

A
Y
B

3628/(Set : B)

(9) 3628/(Set : B)

Write the truth table for the circuit shown in the following Figure. This
circuit acts like which gate ?
A
Y
B

10. lalwpu D;k gksrk gS \ fdlh AM flXuy ds lalwpu dk CykWd vkjs[k cukb,A
2

What is Demodulation ? Give block diagram of detector for AM signal.

[ y?kq mÙkjh; ç'u ]

[ Short Answer Type Questions ]

11. fdlh ,dleku vkosf'kr vuar lery pknj ds utnhd fdlh fcUnq ij fo|qr~ {ks= rhozrk E
ds fy, O;atd fudkfy,A 3

Derive an expression for electric field intensity E near a thin uniformly
charged infinite plane sheet.

12. ,d Js.khc) LCR ifjiFk] ftlesa R = 40 Ω, L = 8H rFkk C = 50 µF gS] dks ,d
ifjorhZ vko`fÙk 240 V ac vkiwfrZ ls tksM+k x;k gSA
(a) òksr dh fdl dks.kh; vko`fÙk ω0 ij vuqukn gksxk \
(b) vuqukn dh voLFkk esa çfrck/kk rFkk /kkjk dh x.kuk dhft,A
3

A series LCR circuit with R = 40 Ω, L = 8H and C = 50 µF is connected
to a variable frequency 240 V ac supply.

3628/(Set : B) P. T. O.

( 10 ) 3628/(Set : B)
(a) What is the angular frequency ω0 of the source at which
resonance occurs ?

(b) Calculate the impedance and current at resonant condition.

13. ;ax dh f}f>jh O;frdj.k ç;ksx ds fy, % (i) O;oLFkk fp=] (ii) fÝat iSVuZ] rFkk
(iii) rhozrk forj.k dk xzkQ cukb,A 3

Draw : (i) schematic diagram, (ii) fringe pattern, and (iii) intensity
distribution graph for Young's double slit interference experiment.

14. vkbaLVkbu dk çdk'k-fo|qr~ lehdj.k fyf[k,A nsgyh vko`fÙk υ0 rFkk fujks/kh foHko V 0 dks
ifjHkkf"kr dhft,A 3

Write Einstein's photoelectric equation. Define the threshold frequency
υ0 and stopping potential V 0 .

15. jsfM;ks,sfDVo {k;rk dk fu;e fyf[k,A v{kf;r ukfHkdksa dh la[;k esa le; ds lkFk cnyko ds
O;atd dks fudkfy,A 3

State the law of radioactive decay. Derive an expression showing the
variation of number of undecayed nuclei with time.

[ nh?kZ mÙkjh; ç'u ]

[ Long Answer Type Questions ]

16. fdlh [kxksyh; nwjchu ls çfrfcac cuus dk ukekafdr fdj.k vkjs[k cukb,A bldh vko/kZu
{kerk dks ifjHkkf"kr dhft, rFkk blds fy, O;atd fyf[k,A 5

3628/(Set : B)

( 11 ) 3628/(Set : B)
Draw a labelled ray diagram showing the image formation in an
astronomical telescope. Define its magnifying power and write
expression for it.

vFkok

OR

rjaxkxz dks ifjHkkf"kr dhft,A gkbxsal ds fl)kUr dks fyf[k,A gkbxsal jpuk dk mi;ksx djrs
gq, fdlh lery rjaxkxz ds lapj.k dks fn[kkb,A 5
Define wavefront. State Huygen's principle. Using Huygen's
construction show propagation of a plane wavefront.

17. n-p-n VªkaftLVj dh lk/kkj.k lajpuk dk fu:i.k dhft,A n-p-n VªkaftLVj dk
ck;lu n'kkZb, rFkk blds dk;Z dk o.kZu dhft,A
5
Give the simple structure of an n-p-n transistor. Show the biasing of an
n-p-n transistor and explain the transistor action.

vFkok
OR

fdlh n-p-n VªkaftLVj ds mHk;fu"B mRltZd foU;kl esa vfHkyk{kf.kd ds v/;;u ds fy,
ifjiFk vkjs[k cukb,A bl foU;kl esa blds % (i) fuos'k vfHkyk{kf.kd o (ii) fuxZr
vfHkyk{kf.kd ds LdSp [khafp,A 5
Draw a circuit diagram to study characteristics of an n-p-n transistor
in common emitter configuration. Draw the sketch of : (i) input
characteristics and (ii) output characteristics for this configuration.

3628/(Set : B) P. T. O.

( 12 ) 3628/(Set : B)
18. ukekafdr fp= dh lgk;rk ls py dqaMyh xSYosuksehVj ds fl)kUr o dk;Zfof/k dk o.kZu
dhft,A 5

Explain the principle and working of a moving coil galvanometer with
the help of a labelled diagram.

vFkok
OR

lkbDyksVªkWu dh dk;Zfof/k dk fp= cukdj o.kZu dhft,A blls fdl rjg ds d.kksa dks Rofjr
fd;k tkrk gS \ 5

Explain the working of a cyclotron using a diagram. What type of
particles are accelerated by it ?

S

3628/(Set : B)