MIN ISTRY OF EDUCAT ION. SINGA PO REin collaboration withUNIV ERSITY O F C AMBRIDG E LOCAL EXAMI NATION S SYNDICATEGen eral Certificate of Education Advanced LevelHigher 2

CA NDIDATENAME

ITIIJCENTRES

INDEXNUMBER NUMBER

9646/02OctoberlNovember 2010

1 hour 45 minutes

Candidates answer on the Quest ion Paper.

No Add itional Materials are required.

READ THESE INSTRUCTIONS FIRST

,-'- - - ---- - - - - - - - - -------- - - - - - - - - - - - - - -.-

.-~iiii PHYSICS0-\i.'- Paper 2 Structured Questions,-.­c~,

Wr ite your Centre number, index number and name on all the work you hand in.Writ e in dark blue or black pen on both sides of the paper.You may use a soft pencil for any diagrams, graphs or roug h working.Do not use staples. paper clips. highlighters , glue or correction lIuid.

Answer all questions .

At the end of the examination , fasten all your work secure ly together.The number of marks is given in brackets [ J at the end of each questionor part questi on.

For Examiner's Use

1

2

3

4

5

6

7

Total

This document consists of 24 printed pages .

.,..'"_. fAlI......,~ '.;;" SIngapore examInations and Asa.ument Board

~

~! UNIVERS ITY ofCAM BRIDGE

'i%jt International Examinat ions

e UCl ES & MOE 2010 DC (SMlSWj 20114/6 (Turn ove r

Data

speed of light in free space .

permeability of free space,

permitt ivity of free space,

elementary charge.

the Planck constant,

unified atomic mass constant,

rest mass of electron.

rest mass of proton.

molar gas constant,

the Avogadro constant.

the Boltzmann constant,

gravitational constant,

acce leration of free fall.

o UClES & MOE 2010

2

c = 3.00 l( 108 m 5 -1

Po =4l{ )( 10-7 Hm-1

Eo =8.65 )( 10-12 Fm- 1

(1/ (36. )) x 10-9 Fm-'

e = 1.60 x 10-111 C

h • 6 .63 x1 0-" Js

u = 1.66 x 10-27 kg

m. = 9.11 )( 10-3' kg

m" = 1.67 l( 10 -27 kg

R· 8.31J K-' mor'

N• • 6.02 x l o"mor'

k· 1.38 x 10-" J I"

G = 6.67 )( 10-11Nm2kg-2

g • 9.81ms' "

964MIl !01NJ10

Formulae

uniformly accelerated motion,

work done on/by a gas,

hydrostatic pressure,

gravitationa l poten tial,

displacement of particle in s.h.m.,

velocity of particle in s.h.m.,

mean kinetic energy of a moleculeof an ideal gas

res istors in series,

resistors in para llel,

electric potential ,

alternating currenUvoltage ,

transmission coefficient,

radioactive decay ,

decay constant,

@UCLES & OE 2010

3

p = pgh

t/J= _ Gmr

x = xosinwt

v =vocos totr--- ...,....

=±w ~X02- x2

E =1 kT2

1/R =1/R + 1/R 2 + . . .

Qv =- ­4 7tCo'

x = xosin (vi

T x exp(- 2kd)

where k = ! 8rr2m(U - E)

~ h2

x = x oexp(-)'I )

). =0.69311'2

964610 10 / 10 [Turn ove r

1

4

(a) State Newton's second law of motion.

... .. ... ... .. ......... .. ... ..... ...... ... .... .. .... ...... .. ... ... .. ...... ... ...... ... .. ... .. .... .. .... .. .... ...... ... .... .... ... ..... . [1]

(b) A car of mass 750kg is travelling "at 25 ms- 1 along a horizonta l road. The brakes areapp lied and the car is brought to rest by an average resistive force F. The car has anaverage decelerat ion of 4.8m s-2•

(I) Show that the resistive force acting on the car is 3600 N.

[1)

(il) Calculate the distance travelled by the car dur ing this deceleration.

distance = m [2]

(iii) Describe, in terms of Newton's third law. the horizonta l forces ac ting on the tyres ofthe ca r and on the road.

... ................................................................................. ............................. .............[2]

(e) The car in (b) now travels at 25 m s-1 down a slope where the angle to the horizontalis 100

• The ca r is brought to rest by applying the brakes. The same resis tive force of3600 N acts on the car.

(I) Explain why the distance the car travels before coming to rest is greater thanin (b) .

......... [1 J

(ii) Calculate the deceleration of the car.

deceleration = m S- 2 [2}

O UCLE$ & MOE 2010 9646/021OiN110

5

2 A car headlamp, rated at 12V and 24W. is used with a constant 12V supply for 1800 s.

(a) Calculate. for the lamp used in this way,

(i) the resistance of the lamp,

resistance = Q (2)

(Ii) the energy transferred in the lamp,

energy = J ltl

(iii) the number of electrons passing through the lamp.

number = [2J

o UCl ES & MOE 2010 9646/02J'01N110 [Turn over

6

(b) The 1-Vcharacteristics of the lamp are investigated using the circuit shown in Fig. 2.1.

12 V

~--1 r--~~~

h--{ A }----'

Fig. 2.1

The variable resistor can be adjusted to have resistance values between 0 and 10 0 .Readings of potent ial difference (p.d.) Vacross the lamp and current 1 in the circuit aretaken. The results obtained are shown in Fig. 2.2.

2.0+t

I ~ :j:j:

I. IT .. .

1.5

I1A ~,

1.0!il++

c!l.' . t

!±0.5 ' r l'

F"Euminer's

U..

i

Ii

I

2 4 6 8 10 12VIV

Fig. 2.2

(i) Explain how the resistance of the lamp can be obtained from Fig. 2.2.

.............................................................................................................................. [I J

C UClES & MOE 2010 9646/02.01N11Q

1,

7

(II) On Fig. 2.3 sketch the variation in resistance of the lamp when the p.d . across itis varied over the range of 2V to 1QV. (Numerical values for the resistance are notexpected.)

resistance I Q

o 2 4 6 8 10 12VIV

Fig. 2.3[2J

(iii) Explain why. in the ci rcuit of Fig. 2.1. the p.d. across the lamp cannot be varied fromo to 12V.

..................................................................................................................................

... ... .. ... ... .... ............. ..... ................. ............. ... ...... ..... ..... ... .. .... .. .......... ... .... ............. [2)

C UCLES & MOE 2010 9646102/01N110 [Turn over

8

3 (a) state Ihe meaning of

(I) diffraction,

... ................ ............. .................- .

......... .......................................... ...... .. ... ... .................................................................

(i1) phase difference.

..................................................................................................................................

(III) coherence.

.......................................- - .(3)

(b) Fig.3.1 shows two microwave emitters M1 and M2. A microwave detector ismoved alongthe line AB.

B

<Q'microwaveemitters

M2

microwavedetector

A

Fig. 3.1

C UCl ES & MOE 2010 964&'02JOINI' 0

9

(I) Explain how interference fringe s are formed along the line AB.

..................................................................................................................................

... ........................................................ .. .....................................................................

.............................. ..... .................................................................... ...........................

.............................................................................................................................. [3J

(Ii) The following changes are made independently. Describe. in each case. the effecton the posi tion and intensity of the fringes.

1. The intensity of the microwaves emitted from both M, and M2 is increased.

...........................................................................................................................

...........................................................................................................................

....................................................................................................................... [2J

2. The phase difference between the microwaves emitted from M, and M2 ischanged by 1t radians.

...........................................................................................................................

...........................................................................................................................

.......................................................................................................................[2J

C UCLES & MOE 2010 96461'OZ01N110 [Turn over

4

10

(a) Define magnetic flux.

...........................................................................................................................................

. .. .. ... ..... .. ...... .. .............. .. ..... ... ... .. ... ... ... .. ... ... .. ....... ... .. ... ... ... . ...... .. ... .. ..... . ... ... ... .. ... ... .. .. . (1]

(b) A coil with 500 turns is placed in auniform magnetic field of flux dens ity 5.0 x 1O-2T.The area of the coil perpendicular to the field is 2.5 x 10-2 m2, as shown in Fig. 4.1.

-;)axiS of rotation

'"Examiller'sUse

magneticfield

II

I

I

Fig. 4.1

area of coil

coil with 500 turns

Calculate the magnetic flux linkage of the coil. Give an app ropriate unit.

magnetic flux linkage = [2]

O UCLES & MOE 2010 9646102JOINI1 0

11

(e) The coil in (b) is rotated around the axi s shown in Fig. 4.1. The flux linkage tPof the coilvaries with time t, as shown in Fig. 4.2.

H+f-j1++++ 1m:!f¥¥ t-'- f+'+t

I+I'f It++ If~ ~ H

m aa1- 0+l-H

¢ 0.5 loW tm·5 2'~J='tlms~

Hct +t++

I t++t 1++

Fig. 4.2

(I) Explain why the flux linkage changes as the coil is rotated.

....................................................................................... ...........................................

................................................... ........................................................................... [1J

(II) Calculate the average B.m.1. induced across the coi l when it rotates through the firstquar ter of a revolution .

e.rn.t, = V [2J

(iii) Explain how the maximum e.rn .t induced across the coil is determined fromFig. 4.2.

................................................. .......................................... .......................................

..................................................................................................................................

..... ............................................ ............................................. ...... .......................... [1J

O UClE$ & MOE 2010 [Turn over

5 <a) (I)

12

Explain the concept of absolute zero on the thermodynamic temperat ure scale.

..................................................................................................................................

........ ............................................... ...... .. ...... .. ...................... ........ ... ......................ltl

F~

Examinllr'sU"

(i1) Stale how the temperature of an ideal gas is related to the energy of the moleculesof the gas.

........................................- -.-..- .

..................................................................................................................................

.. .. .. .... .. .. .. .... .. .... .... .. .. .... .. .. .... .. ...... .... .. ...... .. .. .... .. ...... .... .. .... .. .. .... , [I J

(b) An oven has a volume of 0.064 m3•The pressure and temperature of the air in the oven are1.0 x 105Pa and 27 °C respectively. The mass of one mole of air is 0.030 kg. The airbehaves as an ideal gas.

(i) Calculate the mass of air in the oven.

mass = kg [31

(II) The oven is heated to a temperature of 180°C. The oven door is opened.

Calculate the mass of air that must escape from the oven for the pressure in theoven to return to 1.0 x 1OSPa.

mass = kg [2J

II

I\

O UCLES & MOE 2010

13

6 Therm al conduction is the transfer of thermal energy (heat) through a substance with noovera ll movement of the substance.

(a) Fig. 6.1 shows a solid metal rod of leng th about SOem that has one end maintained at atemperature of 100 °C using a bath of water.

.- - - / metal rod- -- - -

- -r - - -.- -

-- -- - -- - x

bath of walea t 100°C

Fig. 6.1

The rod is in a draughHree room. The apparatus is left unt il the temperature at anypoint along the rod does not chang e. Fig. 6.2 shows the var iation of the temperature 0 ofthe rod with distance x trom the bath of water.

100

-~

90 r

l!:it(We . t=!H+ t++

80

t'70 -' 1. ..

-'

50

• I '

ir

40 H-t+ ++

30o

" '- , H -' H

5 10 15 20 25 30

x/em

C UCLES & MQE 2010

Fig . 6.2

Use Fig. 6.2 to determine the temperature of the rod at a distance x of 17.5cm.

temperature = oC [1J

9646102.01N110 [Turn over

14

(b) The rod in (8) is shortened and placed between two baths 01 water, as shown inFig. 6.3.

I"17.Scm

insulation

"I

bath of watera1100'C - - + i-_ _bath of water

at 4S' C

x Imetal rod

Fig. 6.3

The baths of water are maintained at temperatures of 10Q oC and 45 cC. The length ofthe rod between the baths of water is 17.5cm and the rod is surrounded by insulation.The apparatus is left until the temperature at any point along the rod does not change.Fig. 6.4 shows the variation of the temperature Hof the rod with Ihe distance x from lhehotter bath of water.

I:

,,.

..- !

+I

, I,

I

,,,

" •I

, . ..40

, . .:• . • • , I

: ... I

30o 5.0 10.0

Fig. 6.4

1S.0 20.0 25.0x/em

O UCLES & MOE 20IO 9646/02.101N110

15

(I) The insula tion on the rod is perfect. State the relation between the rate at whichthermal energy enters the rod at 100 °C and the rate at which it leaves the rod.45~ .

..............................................................................................................................(1)

(II) Use Fig. 6.4 to determine the rate of change of temperature with distance alongthe rod (the temperature gradient). Give your answer to an appropriate number ofsignificant figures.

temperature gradient = "C crrr" (2]

(i ii) State why. for any value of x between O.Scm and 17 em, the temperature. as shownin Fig. 6.4, is higher than that shown in Fig. 6.2.

...................... ................... ....... .............. .................. ........ ...................................... [1J

(e) A student thinks that the temperature fJ of the insulated rod in (b) may be inverselyproportional to the distance x along the rod. Show, without drawing a graph, that thisproposal is not correct

(2)

o UClES & MOE 2010 9646102101W10 [Turn over

16

(d) A second student thinks that the temperature (J of the non-insulated rod in (a) dependson the excess temperature of the rod above its surroundings,

Furthermore, the student thinks that the excess temperature reduces exponentially wIthdistance along the rod.

Inordertotest the proposal, the student measures roomtemperature and thencalculatesthe excess temperature Be: and In(8E/ °C) for different values of x. Fig. 6.5 shows somedala for x, e, f!e and In(f!e' °C) ,

room temperature = 20 "c

x/em ere 8e/ oC

0 100 80

2.0 90 70

5.0 n ............

8.0 67 47

12.0 56 36

15.0 49 29

17.5 45 25

20.0 41 21

25.0 35 15

Fig. 6.5

(I) Complete Fig. 6.5 for the distance x = 5.0 em.

In (f!eI"C)

4.38

4.25

............

3.85

3.58 I I3.37 I3.22

I I3.04 II

L 2.70

[1 J

O UCLES & MOE 20 10

17

•

•

25.0x/em

.,

L

20.0

..

: I

I ..• . · .. •- .

· ,, -, . ,

· "

, ·, ,··

., .. ,

..

"

,. .. .I

",

! •

, .,

15.0

.--. .

I .

.,.: II

..

I , I

I ,,--

" -.,

.',

. ~­

I ! ..

10.0

j . ~ .-

I .•. •

- . ,. ,! • •.+

, • ", ,-- ,

--: I •

j ,,, , .I

,•, ; , ,--- t , . --,

"u.. :"1-;-: I , .I . _-I H ..,, .

iI!-I

- • , I

~.........i I I

, I --IIii

- l i I.. , .,

, ..: .

, ,, I I.,

. I

_.. r

.' ;

. ,

5.0

· ,

· .,

· : I

....'.1:

. • I+-"f t • •

, Ir,

. •I

H r,

.:" '

... ~ I•

.,

· I ,.:! I

,;I -I., j I,,.

.'- , "n' : i I:; ; i ,-' . ,

- _ . j....!.• . I I

r t

I 'J. I "

," .'"I; ~ u

.,lt:::!.-

I .f-"'- .

.- II

, !1++ I

II'

3.0

2.5o

_.. t

: ! .,:r: .

4.5 8::: .l l :I -

3.5

Fig. 6.6 is a graph of some of the data of Fig. 6.5.(ii)

Fig. 6.6

C UCLES & MOE 2010 9646J02,Q/NI10 [Turn over

It is proposed that the excess temperature 8E changes with distance x­acco rding to an expression of the form

1.

2.

18

Complete Fig. 6.6 using your data for the distance x = 5.0 em. 11J

where 80 and p are constants.

Explain why the graph 01Fig. 6.6 supports Ihis proposal.

...........................................................................................................................

...........................................................................................................................

...........................................................................................................................

............................................................................. ......................................... [3]

3. Use Fig. 6.6 to determine the constants 80 and p .

°o= ·····························..··.. .... ..···..··· "c- crrr"II - .

[3J

(e) The material of the rod in (8) is a meta l. A similar rod made of wood replaces the metalrod. under the same conditions.

On the axes of Fig. 6.2. sketch a graph to show a possible variation with distance x ofthe temperature 8of this wooden rod. (2)

O UClES &MOE 2010

7

19

A solar panel heats water by absorbing infra-red radiation from the Sun. It consists of anarray of pipes. through which water is passed. The array of pipes is conta ined in a flat boxwith a glass front. as shown in Fig. 7.1.

interna l pipes

water inI "_ - _ - _ - _ - _ -_- _ - - -

'-- - - - - .. \

glass fron t

-,solar panel

... - -- - --- --, ... - - - - --- -... -: ~ -: :. -_ -: -- .._ _ __ __ __ _ J

Fig. 7.1

water out

Design an experiment to determine the efficiency of a model solar panel .

The following equipment is available: a hig h intensity lamp, a variable power supply. anintensity meter for Intra-red radia tion , a model solar panel with a glass front measuring10 cm by 10 cm and any other equipment norm ally availa ble in a school laboratory.

You should draw a labelled diagram to show the arrangement of your apparatus. In youraccount you should pay par ticular attention to

(a) the equipm ent you would use,

(b) the procedure to be followed .

(c) how the power output of the solar panel would be measured,

(d) the control of variables ,

(e) any precautions that would be taken to improve the accuracy of the experiment.[12J '

Diag ram

C UCLES & MOE 20 10 9646t02101N/10 [Turn over