&*r**,r LEi(o$* K*4Name of student:

Physics Teacher:

Physics A

.A2 Syllabus

OCR

H55B replacing 7BB3

Fields , Particles andFrontiers of Physics

Topic: 5.1.25.1.3

Module: G485

Magnetic fieldsElectromagnetism

I

These questions have been taken from recent papers qp to ?049,based on speclfication 3883.

The old specification is a close but not perfect match and someparts of the new specification are not covered. I

.f

Rernember a separate formulaldata sheet is available in theexamination. You may need to look althis to answer thesequestrons

(i)

(ii)

(iii)

e\

t\.t/d\\)

s,\u*'\ ix"v l:."--

I

\

\\_

I

t {a} An aircraft is flying horizontally at a cqnstant speed v close to the North Pole- Fig- 5-1

shows the airciaftliewed irom above. The vertical component B of the Earth's maginetic

field is indicated bY crosses.

O.

Fig.5.1

mark with an arrow the direction of this force-

x B(into page)

tt t-iL,* t: & t\";u"+ un \ h

X

-----l*v

o &cro-J i^"'*t Q

(oppos,k; d!€cho'^ hlnd"cpd e-rl*o".F)

A wire stretches from wing tip P to wing tip Q. Each free electrol'"!*t9."---"'in tlewire experiences a force along the wire. Write down an expression for this force-

F : L:)SgV .tll

tll

t; a -t trfrdlj. i3 i #^r..a*J*

iL {#^dr-rcqc,' t^}b;a.r t O

10fr"i?tA\: b."*:'*E'lt ilc tF*fllJi ' -

-L,

(b) The vertical component B of the Earth's magnetic field is 5.0 x 1O-€T. The aircraftflying ai 200ms-1. The distance PQ between the wing tips is 40m.

(i) Calculate the force exerted by the magnetic field on each electron in the wire.

f* f e.. .. .:l - | *ttrl* =. Lg_.-" € ; .{' h{..'.** lt l't: }t l^ ' ,. '*l';"- 0)

. : e*d-[=. t'e At;'

rorce =...i.:.F.x.t.'l--:l .O * et

(ii) Hence, or othenruise, calculate the voltage induced between the wing tips.

vt'; b it+'l)ii-b U

* $*cF{f*r* ^ ;iftq: F 0

voltage =.........i;-:* O

u

[-lirtal :

t3l

10J

fTurn over

3L Fig.6.1 shows a simple transformer used for demonstrations in the laboratory. lt consists of

two coils linked by a laminated soft iron core. The primary coil is connected to a signalgenerator and the secondary coil to a voltage sensoL interJace and computer. The numberof turns on the secondary coil is double that on the primary coil.

Fig.6.1

(a) (i) Draw on Fig.6.1 the complete paths of two lines of magnetic flux linked withcurrent in the primary coil.

(ii) Define the term magnetic flux. IrU,,r 0 fii-O, Ferctctq'-t lu-r" 0N'.v..'..'........'. " - t'._') " " "

tron core

O c(t'xc'( \oop!

U,wt

b

the

l2l

(iii) Explain how magnetic flux linkage differs from magnetic flux.

o

30

20

10

voltage/V 0

-10

' ,-2o

-30

(iv)

rlYtr

"tv5

ForExamine

Use

+i'*$d..iX:. - -tre*rqt E -fl.v x... li nta4* i n 5**mdcx+ -. -# -t -i. -' - - -. - - - -.

....trr.d*$*r ;. ...v.".1ry#..CI - .CI,llft+i Qptr-olF-- ....-.-.-..--.- t3l

(b) Fig.6.2 shows the computer screen in the demonstration where the number of turns

on the secondary coil is double that on the primary coil-

"time/mS

Fig.6.2

(i) Show that the frequency of the supply is 50 Hz.^

i=rorng {=+ = #,9'=(ii) Calculate the amplitude of the supply voltage,

:- t i) e,';c

amplitude =

*f{s

sa-fi+ ,

no $arLfl\n0ru:*,

ov t21

[otal:12]

/1

\20 3t ,ll 0

[Turn over

S

Read the short passage before ansi'vering the questions below'

Fig.6.1 shows a section of a mass spectrometer. A beam of identical positively-charged

ions, all travelling at the same speed, enters an evacuated chamber through a slit S' A

uniform magnetic field directed verticaliy out of the plane of the diagram causes the ions to

move along the semicircular path Spf. ine beam exits the chamber through the slit at T'

region ofmagnetic field

'k^lr"orl ,\

Clr,hs:t cfC-t c'Li-

(a)

Fig.5-1

draw an arrow to indicate the direction of the force on the ion beamt1l

(b) Describe and explain the changes to the path of the ions for a beam of ions of greater

mass but ihe same speed and charge' -\

r'.\tt'\L/.......-....

"#

For

Examiner's

C)1

L

6

(c) The speed of the singly charged ions is 3'0 x 10s m s-1

density 0.60T. ffre masl of each ion is 4'0 x 10-26kg'

(i) Show that the force on each ion in the beam in

3 x 'l o-14 N.

in the magnetic field of flux

the magnetic field is about

F=BSv QA= t'bl*,o-'ec.

F : O.bS ts \'ior{c*ttc /( 3'QXtor Oc.bs F&_a*x ro-r\ *_ rgnro-\ fr.€d&'l';

12)

(ii) Calculate the radius of the semicircular path'

f= f,ttv'f

f=

f : ff\d t-

t'-

t:o1.>-"*x G:ofto')l^e-t ts tO-rq l'

c. t"*Y

f='l-8tt11r-t\1- -- C 'ilS n",

[D..f :t?.-'.k5 rurradius =

[Total: 12]

[Turn over

ForExamin

Use

r rffrir rrilt ffil ililt ililt llllt ililt ililt til llil

Fig.4..1 shows a square flat coil of insulated wire placed in a region of uniform magneticfield of flux density B. The direction of the field is vertically out of the paper. The coil of sidex has Nturns.

region of uniformmagnetic field

Fig.4.1

(a) {i) Define the term magnetic flux.

f;l*tx: fli:A (nqnrl*{ 1- 8)

(ii)

............... I2l

(b) The coil of side x = 0.020m is placed at position Y in Fi1.4.2. The ends of the1250 turn coil are connected to a voltmeter. The coil moves sideways steadily throughthe region of magnetic field of flux density 0.032T at a speed of 0.10ms-1 until itreaches position Z. The total motion takes 1.0 s.

I lEgl|t iltil !|lilEFilt ilgfl tFllt tlgilltFEt ilgt tEst

0.0 0.01 0.02ltr

:€c,:

:j

)r*-v,

=n-S:i

r'=

-

at^r5

a.t

5=

!]

I

lr-

?r:

J'j

tjj

u

N[}-il,

.,1 '1.,

,i;t|r't*E

i

I

il^ilg

iF,lJ:

L'l

{.{-,t

T=

Itr\J

;H

.300281 1 1.

8

,0.03 r0.04 t0.05 ,0.06 O.07 ,0.08 ,0.09 ,0.10 distance/m

0.020 m+

/c t.,r,

1,

,,. ':j:ii:;:i:.riiirrt i::::ri:::r.:!:.r::.:i

"t ''

region of uniform magneticfield B = 0.0327

coil positioil dt f = 0 coil position at f = 1.0s

Fig.4.2

(i) Show that the voltmeter reading as the coil enters the field region, after f = 0.2 s, isB0 mV. Explain your reasoning fully.

(r\\,

ff\\,

I ':l

{ii) On Fig.4.3, draw a graph of the voltmeter reading against timethe coil from Y to Z. Label the y-axis with a suitable scale.

no n\o$t

$c clAtu'-t]

l3l

'c{.,silcwr

LJ,J

Y

e\i- OA,F*ee,\'

O-L * 0'L{

O tr -o'tO Squt'* pu\:a s'!.o..Pes

Fig.4.3

2824 Juna4

[Total: 10]

[Turn over J

0.10 m s-1

for the motion of

l4J

0 Uynt Pos,

q

A single-tui"n square coil of side 0.050 m is placed in a magnetic field *f flux density I ofmrnnitrrrio il Ft2ATt t tE:r,,,rvee

ia! The coil is placed in thr.ee different orieiitatiCIns io the field as shcwn in Fig' s'1{a}' {b}anri /ni

-il(c)

Fig.6.1

in Fig.6.i(a-i, ii-re piarte of tiie coii is pei'peiidicuiar to the iieid. iri ii-ri, ii is ai43" ia iile

field ind in {l), ii is parallel to the tield. Calcutate ihe value. giv'ing a suitable unii' of ihe

magnetis flux linking the coilfor the pcsiticn shov.'n in

(a)

{i} Fig. 6.1{ai

$= hh "=. *.*sn *'*5 A

= L'f,n iUs

*.GLJ

---^^.1^ 41,,..

illcrgllEtlu ItUA =

T- (iil^ fls' u.i (b) -s = {sFr cc- i*$ = *ia *i^ i+s

0f[.0*t .*(iii) Fig. 6.1ici.

O_)_ 0magnetic tru* = b:f,.I1.0- -"*',..b*!L, isl

Tn*'

g.o*lrs -r 0

masnetic riux = .#.hlt9.Jnn--*-h- ir:I rne

0LJ

r i-

unii..l4'-:& [iiJ r,t*

F$Fgnme./.q

iisr

1r-\tvt

l0

The ccil is rataied in the !"nggnetic fleld to genetate an e.m'f'cf the *.,ariatlcn ef e:rn.f. with tirne !s shawn in Flg' 6.2--

... --,. i .1. .

acrc$s its ends, T{re q,aPhd .;

150

100

50

voltage/mV 0

d *",o'* []mPWdqtime/ms i .

O l-t'hrto Pn"/

til{r,

, t:\til,

-50

-100

-150

F!9. b.2

Cn Fig. €,.Zmark.with an X, a point on the graph ai a ti;ii€ rryhen the flux linking thennil ic e mavirt.,rrrn iil

Give lour reasoning for lrour chalce of position X.

r11"'.i,",."'1" "":".1" " "" " " "" "" ".-"i"':"'_"" """'."""" ":"-"':,'r4J

!l':'

(iii) The rite of rotation of the coilis doubled. Cn Fiq. 6.2 draw a grapir sha,rging ai leasi

twa cycles of ihe e.m.f.'nc"v i'enerafed aciiss the ends cf ihe c'cil. i3i

ITofal:'i1Ia--.-"' "J

ff..-* ^t.a-lrLarrr tasgr

'! t

b (a) Define magnetic ftux density. ff&:.}r* B*ryn*&l+ $svx.*{$Ae*4 U

€1fr*ore" . . I=.gJtrgor.V . . *.-: i*-gt-* C ****.

*(b)

to the plane of the tube.Protons move with a speed v along a circular path within the tube'

evacuatedtube

path ofproton

&ocord hroarJ"*"U" d clr-ck '

(i i)

Fig.5.1

(i) On Fig. 5.1 draw an arrow at P to indicate the direction of the force on the protons

ior them to move in a circle within the tube' t1l

for the force F on a proton in terms of the

F:661s r1l

I(iii)

-+o

For

Examtnef s

Use

IL(iv) Calculate the value of the flux density B needed to contain protons of speed

1 .5 x 107 m s-1 within a tube of radius 60 m. Give a suitable unit for your answer.

F'r*"0

b=ryt = rylvr Lr3 [,bJ F lo-"t X rto-1

t' lrr 'Kldt"l F bO

> O.OO2.!30

B = .-9..1 8Ollp. -unjt. -....f......... tslN,lg"J hJo nr,-u(v) State and explain what action must be taken to contain protons, injected at twice

the speed (2v), within the tube.

v

ool.s

(

[Total: 13]

','

[Turn over

t

i3

This question is about forcing a liquid metal, such as molten sodium' through a tube')\

(a) The liquid metal is in a tube of square cro.ss-section, side w, made of electrically

,,insulating mateiiat, See Fig.5.1. Two electrodes are mounted on opposite sides of the

tube and a magnetic fieH Lf flux density B fills the.region between the electrodes' An

electric currenti purr", across ttre tune between the electrodes, perpendicular to the

magnetic field. The interaction between the current and the field provides the force to

move the liquid.

--==l.- square tubecontainingflowing liquid

ope^ etcl E] [ t"' Fig.5.1

Draw on Fig.5.1 an arrow labelled F to indicate the direction of the force on the

li{uid metallExplain how you determined the direction. {;-"s--#t**.41- W #\#{:*k *"u0

r(i)

(i i)

(iii)

.121

Data for this device are shown below'

B - 0.1571=800Aw=25mm

Calculate the {orce on the liquid metal in the tube'

F:0.\gxg*sr\&5rt\es 03's

force = ...3-:.S..,....... N I2l

For

ExaminefsUse

(b)

r+To monitor the speed of flow of the liquid metal, a similar arrangement of electrodes andmagnetic field is set up further down the tube. See Fig. 5.2. A voltmeter is sonnectedacross the electrodes instead of a power supply.

Fig.5.2

(i) Explain, using the law of electromagnetic induction, why the voltmeter will registera reading which is proportional to the speed of flow of the metal.

.,.4... Votrye .lr.l...id*x*.d.. a.e-nsr. /_nou,*q.. .ryutal_. .

*r it-- s,rf, d=fux linsr O .

State how and explairi why the voltmeterdensity across the tube is doubled.

[Total:10]

2824 Jan(A [Turn over

i{

A nitrogen atom is initially stationary at point P in Fig.5-1, midway between

horizonlal parallel plates in an evacuated chamber. The nitrogen atom becomes

There is an electric field between the plates. lgnore any effects of gravity' \

two largecharged.

(a) Theare

[tq

\1*')'L.:

q$o

direasor

't*-fr L'*"'"',

rds. State with

:

nl(

;

oge

5.1

r nitrc3n.

d.._ - - -r-:€

Fig. t

on ther the ic

H- "--+--.1.

rce c

eon

' "-.'t*...r.S-

forcrge

electricthe cha

i-r...

thenolgn

a, -

>n ofe sig

. !-

ection>n the

t1l

1 .6 x 1o-1e C

.-. ,,'i l

l2l

,-l,

U: ; r-.r-k'F ? d \ ! Icl;-.t- *1- i'

,, ,'-*.-qa, ;-r, &;

nr;i Pt c',t\LrL''alo i t 04 t\ c-1. calculate(c) The electric field strength

separation of the Plates.

r,L: ' : (\ \ --

r ..t \lj

t:gs'

nothe plates is

: d..flt.v.- 5:

-+-l*' .='-.

!a

l2l

the

:,f

o

Far

Exaniner'sUse

(d)

r6

The ion passes through a hole in the lower plate at a speed of 6.5 x 104 m s-]. lt entersa region of uniform magneiic field of flux density O.17 T perpendicularly into the plane ofFig. 5.2.

0 sqni Gc,tttv h. .,3hu dX

X

x

X

X

X

X

X

X

X

x

frvr,',\ a)

hnsmagnetic fieldinto the plane ofthe paper

d) Crn,.s'ut}€'q'h

XX

Fig. 5.2

XX

a)+(i) Sketch on Fig. 5.2 the semicircular path taken by the ion. t1l

(ii) Calculate how far from the hole the ion will collide with the plate. Use data from (b).

.cC

rnr/6,( 6,SllO{

g*'0 f = f.Y,x

bQy'.| = $.3n i0''o

O. t*l x /.bxf0-t1

f '= SScon+ Odu*bcnu i sc = o'tl

:...t.[....... m tst

[Total: 13]

[Turn over

For

Examinef s

Use

iffi This question is about the electron beam inside a television tube.*fi

0 aqu&lt".\

-\P0,GCl

ht,r.r lC*uV ctl

1',ruiY P[rLk+u gtc"€

0 c.sril'"'u.r

-7.0 kv

cathode

ft tti e u[q' k*n*."c/

I r\-(C' 'tnV (-' {-^-' v

J

region ofmagnetic

field

anode

Fig. 5.1 Fig.5.2

section through a simplified model of an electron gun in an evacuated TV

draw electric field lines to represenl the field between the cathode and the

l2l

at negligible speed from the cathode, are acceleratedShow that the speed of the electrons at the anode is about

OV

{tttc.ci Il:>

[!gfr,'-cC'U- \

(a) Fig. 5.1 shows atube.

(i) On Fig. 5.1

anode.

(ii) The electrons, emittedthrough a p.d. of 7.0 kV.

5.0 x 107ms-1.r - ;,P. i ua-

j'

,1 firU/

l2l/\C ,.,rU,-/L {r U*Suu"{.-f'

(b) Some electrons pass through a small hole in the anode. They enter a region of uniform

magnetic field shown by the shaded area in Fig. 5.2. They follow a circular arc in this region

before continuing to the TV screen.

(i) Draw an arrow through the point labelled P to show the direction of the force on the

electrons at this point. t1l

(ii) State the direction of the magnetic field in the shaded area. Explain how you arrived at

your answe. r,\...:.. i............ -.......'1.,...,........,.. i. r........... :*' Y

I lltilr llllt ilffi llil llilllllll lllll lllll lllll llllllll'959752312'

r8

(iii) Calculate the radius of the arc of the path of the electron beam when the value of the

magnetic trux ounJivl= 4.0 * io:tr. I

finv L

r0 e- h"D rc Yt.W| = 3:f flc-],'5- t:3-k*lt"-" 0

oo*to-3x /'("rrd'q

rf\v

sqr

?'+ r/o-L

0radius = .?.:S.*tA..L f+f

{c) The region of uniform magnetic field is created by the electric current in an arrangement of

coils. Suggest how the end of the electron beam is swept up and down the TV screen.

f:t{_;

Choneg* ih$,t nrL.r& $ Cuersnk. i * .cei {s .lD .Lhrrrr ftr &ut'dc*1Le" .-fi Xrel h c"l*cng* rloiJo.efr.c*'* Ote$s:is $"rd tpt*v- So *6e"rgx ddf etftd ft?114rtrt t, Jt*-,.rt (f) r.l

..Lr.f{.....rru... ,....,..,... LAJ

[Total: 13]

lTurn over -

r lilill lilil fifl fiilr ilut ilil1 llilllllll lllll llll llll

F

rtCI

..d\)' )

rF'r\3

(b)

L.o"*roou

I ililil ilil lllll lllll lllll lllll lllll lllll lllll llll llll

i1A spark plug is the device in a petrol engine which ignites the fuel-air mixture, causing an explosion

in the cylinder.

(a) A potential difference of 40 kV is needed across a gap of 0.60 mm to produce the spark which

ignites the fuel vapour. Calculate the magnitude of the electric field strength in the spark gap

just before the spar(/ i'\v

:: ".,; '

t--, \U/

The electrical supply in a motor car is 12V" To achieve 40 kV two coils are wound on tf," same

iron core, shown schematically in Fig.5.1.The secondary coil is in series with the spark gap.

The primary coil is in series with the battery and a switch.=*. C.\e- rl*:Pc:l \ccpt-, , .r,'re- Ytt;*'

\lr'{',tt,'*rr-Lr. f :I -t"cv-a-i

(i''

tron core

12V

coils is the

(iii) Explain why a potential difference is produced

opened"

I-t

sparkgap

C-sb'SEir1:]

(i)

(ii) both

across the spark gap as the switch is

t1l

J

(iv)

zCI -l

Explain how each of the following factors influences the size of the potential differenceacross the spark gap:

...........t21

2 the ratio of the number of turns between the primary and secondary coils.

: Yi;k h.n... m, ..id*o-|. hcf\S.ar.r.nsj:bGfu

I ililil lilil ililillllllllil lllll lllll llllttilll llll llll

Luo.*roou [Turn ou", J

-

I

\\ Fig.5.1 shows a horizontal copper wire placed between the opposite poles of a permanent magnet.The wire is in a state of tension and is clamped at each end. The length of the wire in the field of

flux density 0.032T is 6.0cm.

Fig.5.1

(a) A direct current l is passed through the wire.

clamp

(i) On Fig.5.1 draw and label an arrow F to indicate the direction of the force on the wire.t1l

(ii) Calculate the magnitude F of the force when I = 2.5 A'

A-' ,, L I i{ .= :-- . .*...= -i., :i- ..'

E_T_

jPJ

$i0d

;"qi:Oi. i

.€r

$fi.,$l

icr$tqr$jglLt

i9r(J

ffi{t;i$l',,

i,iQ

:.rgi.0jgr(J:gioie,iq,,9

iga:n

isi€io:n

isilj.n:v,rr!!-,uItii€rlJi.{ii€..t\'.;4

:d::F

',nti:,f,t

!i

le

:i

't:.U

:(:'

rt,:)tA.t:lru

l{i{!i'C

1:{

:T.L

iri€i{',i::i

:7i\:t

i{-ii.}i{

=8c-l

(b) The direct current is changed to an alternating current of constant amplitude and variable

frequency, causing the wire to oscillate. Fig. 5.2 shows how the acceleration of the wire at the

cenire p6int between the poles varies with time when the frequency of the current is at the

fundamental natural frequency of the wire.

750

500acceleration

/ms-2 250

0

-250

-500

-750

Fig.5.2

Uf ti c'rci

Illilil ilill illll lllll lllll lllll lllll llllllllll llll llll

time/ms

r 2:,*(i) Calculate the frequency of the alternating current.

r, :1 ::

f requency

(ii) Explain wheiher the maximum acceleration of all points on the wire beiween the poles isthe same or not. A sketch may help your answer.

. ..........t31

(c) The amplitude of vibration of the wire at the centre point between the poles varies with thefrequency of the current as shown in Fig. 5.3.

7.5

amplitude/mm

.u' t{t tl\*1l' 5.0

l\L\ Lrtst :k

2.5

v ftrsvi \ t\' J -)[-\-l

\',u\tq- f{ri nn """ o

,-\ twiS'-i

s L',1Ui3

Fig.5.3

(i)

(i i)

( iii)

O cffry,Yi,.t<lr"Lq: I l{rc'"tc

Fql u€. tLr-i

5 tr,of-Lr-f'

P}r pr-r;r, &cl

f e{vL

lJa] i'i /-2- - i.rr rl U fLrta L-!'

freouencv/Hz P <r-Lt"r^,'- t{,r f,*.(, /vv ti"'q.

State the term used to describe this effect. .........,..;...;. !-J ...............111

Add the scale to the frequency axis of Fig. 5.3. t1l

A student sticks some small pieces of paper to the wire to see the vibration of the wiremore easily. However this increases the damping of the vibration. On Fig. 5.3 sketch thegraph that you would expect to see for greater damping. l3l

[Total: 13]

r ilfir ililililt ililt ilil ililt ililt ililt ililt ilil ilt

rn over

F-I

z3

This question is about changing the motion of a beam of electrons travelling in a vacuum.

Fig. +.r shows a simple devLelor accelerating or decelerating electrons. lt consists of two parallel

conducting plates, labelled P and Q, each with a hole at its centre.

r\L

beam of

electrons

OV

Fig.4.1

(a) On Fig.4.1. draw at least six arrowed lines to represent the electric field between the plates.

121

(b) The electrons, all travelling at 4.0 x 1 06 m s-1, pass through the holes in P and Q. The plates,

a distance of B.O mm apart, are maintained at 0V and -36V as shown in Fig' 4'1 '

Calculate

(i) the electric field strength E between the plates

- '; AC =. /+ i-CCK-=.rd **f,n_" o

4S*O NC-l [1]E_L_

the magnitude Fof the force on an electron when between the plates

f : u# = t"tlntc-fi F rF5cc O

= 7'Znlitn @ --tbr= '..7.t4..f..fP. ......N I1l

the loss of kinetic energy Ae of each electron between P and Q,

a2- = €-v o_rE

=, i.b F lo-te 7r 3& -rr Ae=.......5:?b llo . ..........J I1I": f.TLrttr

(iv) the decrease in velocity Avof each electron between P and Q.

hr*' F !*nrr^''t A3* Cr\ -r? O ,r.

v*= r4' : a gg =I*,H"?.- **l:l'.o-t= sqr'Tc' -/ q-[; io-"t u

rle \.$Xrd ef= U-V = t1'oh(ob* l'&n'.o'"'-'-* 2'Zrls*

t *v=u

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zqf(c) The plates are rotated through g0". Fig. 4.2 shows the same beam of electrons, travelling

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z{ -lFig. 5.1 shows a soft iron ring of variable circular cross-section. lt has four coils containing 2,3, 4and 5 turns wound around it. The cross-sectional area of the ring is different for each coil.

A d.c. supply is connected across the coil with three turns.

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-aLblWrite down one of the other two quantities in (ii) above. State in which coil this quantityhas the largest value. Give a reason for your answer.

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(b) Fig.7.1 shows a simple a.c. generator used for demonstrations in the laboratory. lt

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Skeich on the grid of Fig.7.2 a typical output voltage which would be seen on theoscilloscope screen. State and explain, using Faraday's law and/or the terms givenin (a), how doubling each of the following factors will alter this output voltage:. ihe speed of rotation of the magnet

. the number of turns on the coilFinally, explain how the output voltage would be different if the soft iron core wereremoved, leaving the magnet and coil in the same positions.

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Quality of Written Communication

Lqln this question, four marks are available for the quality of written communication.

(a) Faraday invented ihe concept of a field of force. Starting from the definitions of electric,gravitational and magnetic field strengths, discuss the similarities and differences betweenthe three force fields.

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Quality of Written Communication [4]

END OF QUESTION PAPER

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