.t. i

-ft

E00z EdvJtvLvzjU i

Y&J

ACVd IXAN EHT OI NO OC

s{JBru 0I IEroI

[sq.tuut g]

'rolloudeo slrg ur paJots ,(8raua (l)

[s4reur gJ

rolrcedec srtll Jo acuulrrsduo (l)

aql elBlnrleJ

n 00S Jo eruereJJrp lpnualod e ol pa8reqc sl ru ._0I x 0-Iuonerudas eteld pu€ zru e_0I x 0'S BerE Surneq :orlcuduc peilU-rle .aleldi-lagered

V (c)

[speu g]

'selJss

ul 'tJ pue zJ'13 'stoltcudec eeJql Jo J, 'aJuulrJ?duc ptol eril JoJ uorsss:dxe u? e^ue6l (q)

[ 4reur 1J

aflqfl- E -

2a&'�V'r'T'f'

' ,pBJEJ, aql augeq (e) 'I

- 4 -

2. (a) Define EACH of rhe following terms:

(i) Magnetic flux:

[1 mark ]

(ii) Tesla:

[1 mark ]

(b) State

(i) Faraday's Law

[1 mark ]

(ii) Lenz's Law.

[1 mark ]

002474/CAPE 2003GO ON TO TF{E NEXT PAGE

(c) Two conducting rods are joined

- 5 -

at right angles to each other as shown in Figure l.

Conductingbar

o Conducting rods

o r .

. Figure I

A conducting bar in contact with the rods starts at the vertexvelocity (v) of 4-20 m s-r arong them as shown. A magneticis directed perpendicularly our of the page.

Find the

(i) area of the triangle which is formed at 2 seconds by the conducting bar andconducting rods

[2 marks](ii) magnetic flux through the triangle at seconds

(iii) electromorive force (e.m.f.) induced in rhe

[2 marks]

moving rod at 2 seconds.

[2 marksl

Total l0 marks

GO ON TO THE NEXT PAGE

and moves with a consrantfield of magnitude 0.450 T

002474|CAPE 2003

- 6 -

3. (a) Write an expression for the total resistance, Rr, of three resistors Rt, Rz and R3, in

parallel.

[1 mark I

(b) State Ohm's Law.

ll mark I

(c) Explain the difference between the electromotive force (e.m.f.) and the terminal potentialdifference (p.d.) of a battery.

[2 marks]

002474|CAPE 2003GO ON TO T}IE NEXT PAGE

(d)

- 7 -

A set of measurements were made using the circuit of Figure 2.

Figure 2

Table I below shows some of the results obtained.

R v I

0 0 O.15 A

300 a r 0 voo

Thble I

Fill in the blank spaces in rhe tabre with the missing data.

[6 marks]

Total 10 marks

GO ON TO THE NEXT PAGE002474|CAPE 20A3

8 -

4. (a) Explain what is meant by EACH of the following:

(i) P-type semiconductor

(ii) N-rype semiconductor

t i i i ) Doping, as appl ied to semiconduclors

(iv) Depletion region

O) Suggest ONE application of a p-n junction diode.

lL mark I

[1 mark I

[1 mark ]

[1 mark ]

[1 mark ]

002474/CAPE 2003GO ON TO TTIE NEXT PAGE

- 9 -

(c) Figure 3 shows a combination of two silicon diodes in a circuit.

Figure 3

The characteristic I - v curve for the diodes is shown in Figure 4.

uA z.s2.0

1.5

1.0

0.5

00 0.2 vlv

( i) Calculate the

a ) V i =

voltage, 7r, when

[2 marksJ

b) Vr = - 10-0V.

[1, mark ]

1000 o

vo

2.0 v -r -1- z.o vI

002474|CAPE 20A3GO ON TO T}TE NEXT PAGE

- 1 0 -

(ii) Sketch the output when V, = 10 Sin 0)t, where c0 = 100 rad s-1, includingappropriate numerical values on the scales.

[2 marks]

Total 10 marks

002474/CAPE 2A03GO ON TO THE NEXT PAGE

(a)5 .

t l

In the space provided below sketch a typicalamplif ier.

gain frequency curve for an operational

[3 marks]

(b) What is meant by a 'virtual earth' rn an operational amplifier circuit?

[1 mark ]

(c) State ONE effect of positive feedback in an operational arnplifier circuit.

[1 mark ]

002474|CAPE 2W3GO ON TO TFM NEXT PAGE

(d)

. 1 , 2 -

Figure 5 shows a cascade amplifier circuit-

100kfi 500ko

Figure 5

Calculate the

(i) net gain of the circuit

[4 marks]

(ii) output voltage, Vr, when Vi = 0.01,V.

[1 mark ]

Total 10 marks

002474/CAPE 2003GO ON TO THE NEXT PAGE

(a)6.

1 3 -

(i) Arithmetic operations are usually performed by adders. A half adder circuitis used to add the l 's column in binary addit ion. Write the truth table for ahalf-adder.

[2 marksl

You are provided with an Exclusive-OR (EX-OR) gate and an AND gate fordesigning a half adder circuit. Draw a circuit diagram to show how these couldbe arranged.

[2 marksJ

( i i )

a02474tCAPE 2003GO ON TO THE NEXT PAGE

- 1 4 -

(b) Draw a circuit diagram to show how the NAND gares could be used to build a flip-flop.

[1 mark ]

(c) Write the truth table for the circuit shown in Figure 6, indicating the output at X, Y andZ"

Figure 6

[3 marks]

GO ON TO THE NEXT PAGE002474/CAPE 2003

- l ) -

(d) Draw a simple logic circuit to represent the rruth table below in which A and B areinputs and X is the outpur.

A B X0 0 00 1 0r 0 t

[2 marks]

Total 10 marks

002474/CAPE 2403GO ON TO THE NEXT PAGE

1 6 -

7. (a) State THREE experimental facts about the photoelectric effect which support theparticulate (photon) model of light.

[3 marks]

(b) When ul t raviolet l ight is incident on an insulatecl metal p latc, thc plate emits electronsfor a while and then stops.

Explain why the process'eventually stops.

[1 mark ]

(c) The energy level scherne for a newly discovered one-electron element is shown inFigure 7. The electron is in its ground state.

n = 4

n = 3

n = 2

n = l

-2 eY

-5 eV

-10 eV

-20 eV

Figure 7

(i) Determine the amount of energy it will take to ionize an electron from theground state.

[1 mark 1

(ii) State what will happen if a 6 eV photon srrikes the atom.

[1 mark 1

GO ON TO THE NEXT PAGE00247 lCAPE 2003

- t 7 -

(d) An electron makes a transition from the n = 3 state to the n = I state.

(i) Calculate the frequency of radiation emitted.

[2 rnarks]

(ii) Calculate the wavelength of radiation emitted.

l l mark 1

(iii) In which region of the electromagnetic spectrum would this radiation be found?

[1 mark ]

Total 10 marks

002474/CAPE 2003GO ON TO THE NEXT PAGE

8.

- 1 8 -

(a) (i) Explain the principle by which a continuous X-ray spectrum is produced.

[2 marksJ

Why is a vacancy in an inner electron shell usually required for an atom to emitan X-ray photon?

(ii)

(b) A beam of X-rays, of intensity /r, is incident on a slab of materialabsorption coefficient prr, as shown in Figure 8 a.

[2 marksJ

of thickness x, and

(i)

< - x r €

Figure 8 a

Write an expression for the emerging intensity, /, in terrns of /p, 1t1 and x,.

[1 mark I

o02474tCAPE 2003GO ON TO TIfi NEXT PAGE

(ii)

_ 1 9 _

A second slab of material, of thickness x2 and absorption coefficient pr, isplaced alongside the first slab as shown in Figure 8 b.

* tr-> (,-- t r-

Figure 8 b

Show that the Intensiry, /, is given by

I = Io e-(ts,t, * Frtr)

[3 marks]

= 8.0 rn-I,

a)

b) Calculate the value of / where Io =

xt = 2.0 mm, p2 - 4.0 m-l , x2 =500 Wm-2, ltt

4r0 mm"

[2 marksl

Total 10 marks

* r r _ >

002474|CAPE 2003GO ON TO TI{E NEXT PAGE

(a)9,

. 20 -

Explain what is rneant by EACH of the following tenns:

(i) Nuclear fission

[1 mark J

(ii) Nuclear fusion

[1 mark J

(iii) Binding energy

(b)

[1 mark ]

"r1u. How many of EACHThe nucleus of an atom of uranium can be represented byof the following particles are there in the nucleus?

(i) Protons

[1 mark J

(ii) Neutrons

lL mark J

002474/CAPE 2003GO ON TO THE NEJ(T PAGE

-21 -

(c) An induced fission reaction is described by the following equation.

in * '71ru - 23n6rtJ* -+ tflna + 3?tt * 3!n + E

Masses:

'llru = 235.0439 u

'!|n" = 140.9141 u :

t2*, = 9l .9262 u

fn = 1.0087 u

I u = 931.5 MeV/cz

Calculate

(i) the energy E, in eV released during the reaction

the energy, in eY of EACH neutron producbd in the reaction.

END OF TEST

[4 marks]

(ii)

ll. mark J

Total L0 marks

002474|CAPE 2003