jayc promo

8/12/2019 jayc promo

1/23

PIONEER JUNIOR COLLEGEPromotional Examination

PHYSICS 9646/02Hig!r 2

Paper 2 Structured Questions

7 October 2009

2 o"r# $% min"t!#Candidates answer on the Question Paper.No Additional Materials are required.

RE&' (HESE INS(RUC(IONS )IRS(

rite !our na"e# class and inde$ nu"ber on all the wor% !ou hand in.rite in dar% blue or blac% pen.&ou "a! use a so't pencil 'or an! dia(ra"s# (raphs or rou(h wor%in(.

)o not use staples# paper clips# hi(hli(hters# (lue or correction 'luid.

Answer allquestions.

At the end o' the e$a"ination# 'asten all !our wor% securel! to(ether.*he nu"ber o' "ar%s is (i+en in brac%ets , - at the end o' each question or part question.

)or Examin!r*# U#!

$ 7

2 /

+ 1

4 0

% 0

6 2

,

- 1

(otal 90

*his docu"ent consists o' 22printed pa(es.

.("rn o!r

Nam! Cla## In!x N"m1!r


2/23

'ata

speed o' li(ht in 'ree space# /000.3 =c " s4

per"eabilit! o' 'ree space# 70 01

= 5 "4

per"itti+it! o' 'ree space# 20 0/./ = 6 "4

( )( ) 903 = 6 "4

ele"entar! char(e# 900. =e C

the Planc% constant# 3103. =h 8 s

uni'ied ato"ic "ass constant# 270. =u %(

rest "ass o' electron# 30.9 =e

m %(

rest "ass o' proton# 2707. =pm %(

"olar (as constant# 3./=R 8 4 "ol4

the A+o(adro constant# 23002. =A

N "ol4

the :olt;"ann constant# 2303/. =k 8 4

(ra+itational constant# 07. =G N "2 %(42

acceleration o' 'ree 'all# /.9=g " s42

)orm"la!

2


3/23

uni'or"l! accelerated "otion# 2

2

atuts +=

asuv 222+=

wor% done onb! a (as# VpW =

h!drostatic pressure# ghp =

(ra+itational potential#r

Gm=

displace"ent o' particle in s.h.".# txx sin0=

+elocit! o' particle in s.h.".# tvv cos0=

22

0

xx =

resistors in series# ...2 ++= RRR

resistors in parallel# ... 2 ++= RRR

electric potential#r

QV

01=

alternatin( current+olta(e# txx sin0=

trans"ission coe''icient# ( )kdT 2e$p = where( )2

2/

h

EUmk

=

radioacti+e deca!#


4/23


5/23

? ........................................ ,3-

2 A tile o' "ass 270 (# initiall! at rest# slides down a roo' 'or a distance o' 3./ " be'ore'allin( o'' the roo'. *he tile e$periences a resisti+e 'orce o' 0.10 N while slidin(. *he roo'is inclined at an an(le o' 2 to the hori;ontal# and its ed(e is 2.3 " abo+e the (roundas shown in 6i(. 2..

%

2

tile

roo'

(round

2.3 "

.("rn o!r


6/23

)ig 2$

a3 Calculate the acceleration o' the tile as it slides down the roo'.

acceleration ? ........................................ " s42 ,2-

13 )eter"ine the speed o' the tile Bust as it lea+es the roo'.

speed ? ........................................ " s4 ,2-

53 )eter"ine the ti"e ta%en 'or the tile to hit the (round a'ter lea+in( the roo'.

6


7/23

ti"e ta%en? ........................................ s ,2-

3 )eter"ine the hori;ontal distance 'ro" the ed(e o' the roo' at which the tile lands.

hori;ontal distance? ........................................ " ,2-

+ a3 A c!linder with a piston contains 0.00 "oles o' an ideal (as at 000.1 Pa and

300 . *he (as under(oes 3 processes

=< e$panded at constant pressure to twice its ori(inal +olu"eD and then=2< co"pressed at constant te"perature to its ori(inal +olu"eD and 'inall!=3< cooled at constant +olu"e to its ori(inal pressure.

i3 Calculate the ori(inal +olu"e o' ideal (as in the c!linder.

,

.("rn o!r


8/23

+olu"e ? ........................................ "3 ,2-

ii3On 6i(. 3.# s%etch the series o' processes =


9/23

wor% done b! the (as? ........................................ 8 ,2-

13 i3 )e'ine specific heat capacity.

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

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

........................................................................................................................... ,2-

ii3 @n a heatin( e$peri"ent# ener(! is supplied at a constant rate to a liquid in a

bea%er o' ne(li(ible heat capacit!. *he te"perature o' the liquid rises at 1.0 per"inute Bust be'ore it be(ins to boil. A'ter 10 "inutes all the liquid has boiled awa!.6or this liquid# calculate the ratio o' its speci'ic heat capacit! to its speci'ic latentheat o' +apori;ation.

ratio ? ........................................ 4 ,3-

4 a3 6i( 1. shows 'i+e identical car(o bo$es# each o' "ass m# spaced out in a strai(htline on a 'rictionless hori;ontal sur'ace. All 'i+e bo$es are stationar! initiall!.

)ig 4$

9

A : C ) E

.("rn o!r


10/23

:o$ A is (i+en a push and it "o+es towards bo$ : at a +elocit! ov . A'ter collidin(

with bo$ :# bo$ A and : continues to "o+e 'orward until all 'i+e bo$es are touchin(one another and "o+in( at a co""on +elocit!.

i3 State thepricip!e of coservatio of mometum.

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

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

........................................................................................................................... ,-

ii3 E$press the co""on 'inal +elocit! o' the 'i+e bo$es in ter"s o' ov .

,2-

iii3 Calculate the ratio o' the %inetic ener(ies o' the 'i+e bo$es be'ore the collisionto that a'ter the collision.

ratio ? ........................................ ,-

13 6i( 1.2 shows the 'i+e bo$es at rest in a strai(ht line on a s"ooth hori;ontal sur'acewith their adBacent 'aces in contact.

$0

A : C ) EP


11/23


12/23

,-

3 *he car(o bo$es contain brea%able ite"s and are to be brou(ht onto a hori;ontalsur'ace without brea%in( the contents inside. A 'rictionless ra"p F& is added ontora"p PQ with an inclined an(le # where is s"aller than . *his helps to

reduce the i"pact on the bo$es as the! "o+e 'ro" ra"p PQ to the hori;ontal sur'ace# asshown in 6i(. 1.1.

)ig 44

@' the bo$es are released 'ro" the sa"e hei(ht as be'ore# e$plain how the insertiono' ra"p F which has a s"aller (radient# helps to reduce the i"pact on the bo$es.

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

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

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

................................................................................................................................. ,2-

$2

A:

C)

E

P

Q

F

&


13/23

% a3 A helicopter tra+ellin( at a hei(ht o' 3000 " abo+e the (round dra(s alon( a 1.0 %("ass A that is suspended 'ro" the helicopter at P with a li(ht ine$tensible cord o'

len(th 0.0 ". A hori;ontal dra( 'orce "# o' 300 N is e$erted on the "ass as the

helicopter 'lies at constant speed$*his causes the cord to be inclined at an an(le o' 'ro" the +ertical as shown in 6i(. ..

)ig %$

i3 )raw a labelled 'reeGbod! dia(ra" o' all the 'orces actin( on "ass A.

,-

ii3 E$press# in ter"s o' #

$ the cloc%wise "o"ent due to the wei(ht o' "ass A about point P$

,-

2 the antiGcloc%wise "o"ent due to "# about point P$

,-

$+

P

"ass A

0.0 "


14/23

iii35ence or otherwise# deter"ine the an(le o' inclination .

? ........................................ ,2-

13 @n the helicopter# a "an detaches the cord at P and allows "ass A to 'all 'reel! awa!

'ro" the helicopter. At the sa"e ti"e# a si"ilar "ass :# wei(hin( 7.0 %(# waspushed o'' 'ro" the helicopter.

Mass A attains a +ertical ter"inal +elocit! o' 0/ %" hH soon a'ter lea+in( thehelicopter. Mass : also attains ter"inal +elocit! and continues to 'all +erticall!

towards "ass A. @t "a! be assu"ed that the +iscous dra( 'orce v# e$perienced b!

a 'allin( "ass is proportional to 2v # where vis the speed o' the "ass. >pthrust due

to air "a! be i(nored.

i3 )eter"ine the ter"inal +elocit! that "ass : would attain assu"in( that itshori;ontal +elocit! is ne(li(ible.

ter"inal +elocit! ? ........................................ " s4 ,3-

$4

.("rn o!r


15/23

ii3 )raw the path ta%en b! "ass A 'ro" the "o"ent it was released till it reaches the(round.

,2-

$%

.("rn o!r


16/23

6 A .30 %( bloc% is released 'ro" point A as shown in 6i( .. *he trac% is 'rictionless#e$cept 'or the rou(h sur'ace between : and C# which has a len(th o' .00 ". *he bloc%tra+els down the trac%# hits a sprin( at ) o' 'orce constant k ? 10 N "H# andco"presses the sprin( 0.10 " 'ro" its equilibriu" position be'ore co"in( to rest"o"entaril!.

)ig 6$

a3 Calculate the speed o' the bloc% at :.

speed ? ........................................ " s4 ,2-

13 Calculate the ener(! stored in the sprin( a'ter the bloc% has co"pressed the sprin('ull!.

ener(! stored? ........................................ 8 ,2-

$6

2.0 "

A

:

)

C.00 "


17/23

53 On 6i(. .2# s%etch a labelled (raph to show the +ariation o' the 'orce #e$erted b!the bloc% on the sprin( a(ainst the co"pression o' the sprin(x.

)ig 62 ,2-

3 Calculate the ener(! lost due to 'riction# assu"in( all other 'or"s o' ener(! lossesare ne(li(ible.

ener(! lost? ........................................ 8 ,2-

!3 5ence# calculate the a+era(e 'rictional 'orce actin( a(ainst the bloc%.

a+era(e 'rictional 'orce? ........................................ N ,2-

3 @' the bloc% rebounds and "o+es le'twards past C a'ter the sprin( deco"pressesitsel'# calculate the distance 'ro" C at which the bloc% will 'inall! co"e to rest.

$,

x "

# N

0


18/23

distance ? ........................................ " ,2-

$-

.("rn o!r


19/23

, a3 *he (ra+itational 'ield stren(th o' the Earth at its sur'ace is 9./ N %(H.

Show that

i3 the acceleration o' 'ree 'all at the sur'ace o' the Earth is 9./ " sH2.

,2-

ii3N %(H

is equi+alent to " sH2

in S@ base units.

,2-

13 A satellite o' "ass morbits the Earth o' "ass %and radius Er . *he radius o' the

orbit is R. *he satellite and the Earth "a! be considered to be point "asses withtheir "asses concentrated at their centres. *he! "a! be assu"ed to be isolated inspace.

i3 E$plain wh! the satellite does not "o+e in the direction o' the (ra+itational 'orce.

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

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

........................................................................................................................... ,-

$9


20/23

ii3 )eri+e an e$pression# in ter"s o' Er # 'or the radius o' the orbit Rso that the

an(ular +elocit! o' the satellite is equal to the an(ular +elocit! o' the Earth.E$plain !our wor%in(.

,1-

iii3State two circu"stances under which a satellite at this distance will be a(eostationar! satellite.

$ ............................................................................................................................

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

2 ............................................................................................................................

.......................................................................................................................... ,2-

53 As a result o' air resistance# the satellite loses ener(! as it orbits the Earth. E$plainthe e''ect o' this chan(e on

i3 the radius o' the orbit#

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

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

................................................................................................................................. ,2-

ii3 the speed o' the satellite.

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

20


21/23

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

................................................................................................................................. ,2-- a3 )e'ine simp!e harmoic motio.

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

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

................................................................................................................................. ,2-

13A +ertical sprin( supports a "ass %o' 0./0 %( as shown in 6i(. /.. *he "ass isdisplaced +erticall! upwards b! 2.0 c" and then released. @t reaches the lowestposition in 0.27 s and oscillates in si"ple har"onic "otion.

)ig -$

At the point when it is released#

i3 deter"ine the acceleration o' the "ass %#

acceleration ? ........................................ " s42 ,3-

ii3 deter"ine the "a(nitude o' the net 'orce actin( on the "ass# and its direction.

2$

%

.("rn o!r


22/23

net 'orce? ........................................ N ,-

direction? ........................................ ,-iii3deduce the tension in the sprin(.

tension? ........................................ N ,2-

53 *he sprin( s!ste" in 6i( /. is now connected to a +ariable 'requenc! +ibrator as

shown in 6i(. /.2.

)ig -2

*he +ibrator itsel' has constant a"plitude. As the 'requenc! is +aried# the a"plitudeo' oscillation o' the "ass %(oes throu(h so"e chan(es.

i3 On 6i(. /.3# s%etch a wellGlabelled (raph to show the +ariation o' a"plitude o'"ass %with the 'requenc! o' the +ibrator.

22

%

Iariable 'requenc! +ibrator


23/23

)ig -+ ,3-ii3*he pheno"enon which is illustrated in 53can cause considerable en(ineerin(

proble"s. State one such proble" and su((est a wa! in which it can beo+erco"e.

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

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

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

........................................................................................................................... ,2-

2+

.("rn o!r

jayc promo

Documents