AKADEMI 2020M3

MODUL 3 50 FIZIK SPM

KEELEKTROMAGNETAN, ELEKTRONIK DAN KERADIOAKTIFAN

1 Diagram 1.1 and Diagram 1.2 show the pattern of an electromagnetic field formed by
iron filing when the solenoids are connected to the battery.
Rajah 1.1 dan Rajah 1.2 menunjukkan corak medan elektromagnet terbentuk oleh
serbuk besi apabila solenoid disambungkan ke bateri.

Diagram 1.1 Diagram 1.2
Rajah 1.1 Rajah 1.2

(a) What is the meaning of electromagnet?
Apakah yang dimaksudkan dengan elektromagnet?

……………………………………………….....................................................................
[1 mark]

(b) A plotting compass is located at P in Diagram 1.1.
By using an arrow, mark the direction of the pointer of the compass.
Satu kompas memplot diletakkan pada P dalam Rajah 1.1.
Dengan menggunakan anak panah, tandakan arah penunjuk jarum kompas.
[1 mark]

(c) Based on Diagram 1.1 and Diagram 1.2, compare;
Berdasarkan Rajah 1.1 dan Rajah 1.2, bandingkan;

(i) the number of turns of the coil.
bilangan lilitan gegelung.

.………………………..............................................................................................
[1 mark]

(ii) the number of iron filing lines.
bilangan garis serbuk besi.

………………………………....................................................................................
[1 mark]

(iii) the magnitude of current passing through the solenoid.
magnitud arus yang melalui solenoid.

…………………………………………………………………………………………….
[1 mark]

AKADEMI SPM 2020 JPNT

MODUL 3 51 FIZIK SPM

(d) State the relationship between the number of turns of the coil and the strength of
the magnetic field.
Nyatakan hubungan antara bilangan lilitan gegelung dan kekuatan medan magnet.

..……………………………………………........................................................................
[1 mark]

(e) Explain what happen to the strength of the electromagnet if a soft iron core is
inserted in the solenoid?
Terangkan apakah yang berlaku kepada kekuatan elektromagnet jika teras besi
lembut dimasukkan kedalam solenoid?

…………………………………………….........................................................................
[2 marks]

2 Diagram 2.1 shows the position of hand to represent Fleming’s Left Hand Rule.
Rajah 2.1 menunjukkan keadaan tangan bagi mewakili Petua Tangan Kiri Fleming.

Diagram 2.1
Rajah 2.1

(a) Write the physics quantities which represent by the thumb, index finger and middle
finger in the boxes provided in Diagram 2.1.
Tuliskan kuantiti fizik yang diwakili oleh ibu jari, jari telunjuk dan jari tengah dalam
petak-petak yang disediakan dalam Rajah 2.1.
[2 marks]

(b) Diagram 2.2 shows a copper rod XY placed on a copper rail placed between poles
of a permanent magnet.
Rajah 2.2 menunjukkan sebatang rod kuprum XY berada di atas landasan kuprum
diletakkan antara kutub-kutub sebuah magnet kekal.

Diagram 2.2
Rajah 2.2

AKADEMI SPM 2020 JPNT

MODUL 3 52 FIZIK SPM

(i) Underline the correct answer in the bracket to complete the sentence below.
When the d.c power supply is switch on, the current in the copper rod flow from
(X to Y, Y to X)

Garis jawapan yang betul dalam kurungan untuk melengkapkan ayat di bawah.
Apabila bekalan kuasa a.t. dihidupkan, arus dalam rod kuprum mengalir dari
(X ke Y, Y ke X)

[1 mark]

(ii) Mark with an arrow on Diagram 2.2, the direction of the catapult force on the
copper rod.
Tanda dengan satu anak panah pada Rajah 2.2, arah daya lastik ke atas rod
kuprum itu.
[1 mark]

(iii) What happen to the magnitude of the catapult force when the strength of the
magnet is increased.
Apakah yang berlaku pada magnitud daya lastik itu apabila kekuatan magnet
ditambah?

………………..………………………………………………………………………….
[1 mark]

(c) On Diagram 2.3 draw the catapult field pattern formed between the poles of the
magnets.
Pada Rajah 2.3 lukis corak medan lastik yang terbentuk antara kutub-kutub
magnet.

Diagram 2.3
Rajah 2.3

[2 marks]

(d) State one method to reverse the direction of the catapult force.
Nyatakan satu kaedah untuk menyongsangkan arah daya lastik itu.

………………………………………………………………………………………………….
[1 mark]

AKADEMI SPM 2020 JPNT

MODUL 3 53 FIZIK SPM

3 (a) Diagram 3.1 shows a relay used in an electrical circuit.
Rajah 3.1 menunjukkan satu geganti yang digunakan dalam satu litar elektrik.

Diagram 3.1
Rajah 3.1

(i) What is the function of a relay?
Apakah fungsi geganti?

.....................…………………………………………………..…………………………
[1 mark]

(ii) Explain what will happen when an electric current flow in the main circuit?
Terangkan apakah yang akan berlaku apabila arus elektrik mengalir dalam litar
utama?

.......................………………………………………………..…………………………

....................…………………………………………………..…………………………
[2 marks]

(b) What is component Q?
Apakah komponen Q?

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

(c) Suggest two methods to increase the strength of the relay.
Cadangkan dua kaedah untuk menambah kekuatan geganti.

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

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

AKADEMI SPM 2020 JPNT

MODUL 3 54 FIZIK SPM

4 Diagram 4.1 show a coil PQ, made of copper wire is connected to a sensitive
galvanometer to study the effect of electromagnetic induction.
Rajah 4.1 menunjukkan suatu gegelung PQ, diperbuat daripada dawai kuprum
disambungkan kepada suatu galvanometer peka untuk mengkaji kesan aruhan
elektromagnet.

Diagram 4.1
Rajah 4.1

(a) What is the meaning of
Apakah maksud

(i) Electromagnetic induction
Aruhan elektromagnet

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

[1 mark]

(ii) Faraday’s Law

Hukum Faraday

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

(b) A small permanent magnet which is connected to the end of an elastic spring
oscillates in and out of the end, P, of the coil as shown in Diagram 4.1.
Suatu magnet kekal kecil yang disambungkan pada hujung suatu spring elastik
berayun masuk dan keluar hujung P gegelung itu seperti ditunjukkan dalam
Rajah 4.1

(i) Describe what happens to...
Perihalkan apa yang berlaku kepada...

(1) the circuit containing coil PQ,
litar yang mengandungi gegelung PQ.

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

(2) the pointer of the galvanometer.
jarum penunjuk galvanometer itu.

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

AKADEMI SPM 2020 JPNT

MODUL 3 55 FIZIK SPM

(ii) What is the magnetic pole formed at the end, P, when the permanent magnet is
moving away from P?
Apakah kutub magnet yang terbentuk pada hujung P apabila magnet kekal
berayun menjauhi P?

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

(iii) Name the physics law you have used to determine your answer in (b)(ii).
Namakan hukum fizik yang anda gunakan untuk menentukan jawapan anda
dalam (b)(ii).

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

(c) (i) It is found that the oscillation of the permanent magnet stops after a few
seconds. What happens to the kinetic energy of the permanent magnet when it
stops oscillating?
Didapati ayunan magnet kekal berhenti selepas beberapa saat. Apakah yang
berlaku kepada tenaga kinetik magnet itu apabila ia berhenti mengayun?

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

(ii) State two modifications which should be made in the apparatus set up as
shown in Diagram 4.1 to increase the magnitude of the induced current.
Nyatakan dua modifikasi yang perlu dibuat pada susunan radas dalam
Rajah 4.1 supaya magnitud arus aruhan dapat ditingkatkan.

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

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

(d) Name one electrical appliance which operates on the principle of electromagnetic
induction.
Berikan nama satu alat elektrik yang berfungsi berasas prinsip aruhan
elektromagnet.

.........………………………………………………………………………………………......
[1 mark]

AKADEMI SPM 2020 JPNT

MODUL 3 56 FIZIK SPM

5 Diagram 5.1 shows a laminated soft iron core is wounded with insulated copper wire. An
a.c. voltage of 240 V is connected to primary coil with 3000 turns of wire and a bulb 12V
60W is connected to the secondary coil.
Rajah 5.1 menunjukkan satu teras besi lembut berlapis dililitkan dengan dawai kuprum
bertebat. Voltan a.u 240 V disambungkan kepada gegelung primer dengan 3000 lilitan
dawai manakala satu mentol 12V 60W disambungkan kepada gegelung sekunder.

Diagram 5.1
Rajah 5.1

(a) What type of transformer is shown in Diagram 5.1?
Apakah jenis transformer yang ditunjukkan dalam Rajah 5.1?

.........………………………………………………………………………………………......
[1 mark]

(b) Why the soft iron core is used in the transformer?
Mengapakah teras besi lembut digunakan dalam transformer tersebut?

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

(c) Determine the number of turn in the secondary coil, if the bulb lighted up with normal
brightness.
Tentukan bilangan lilitan gegelung sekunder jika mentol menyala dengan kecerahan
normal.

[2 marks]

(d) When the primary coil in Diagram 5.1 is connected to direct current (d.c).
Bila gegelung primer disambung kepada arus terus (a.t).

(i) What happens to brightness of the bulb?
Apakah yang berlaku kepada kecerahan mentol?

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

(ii) Give the reason for your answer.
Nyatakan sebab jawapan anda.

.............………………………………………………………………............................
[1 mark]

AKADEMI SPM 2020 JPNT

MODUL 3 57 FIZIK SPM

6 Diagram 6.1 shows a circuit breaker.
Rajah 6.1 menunjukkan sebuah pemutus litar.

Diagram 6.1
Rajah 6.1

(a) (i) What is meant by electromagnet?
Apakah maksud elektromagnet?

[1 mark]

(ii) Explain how the circuit breaker disconnected the circuit when a lightning occurs.
Terangkan bagaimana pemutus litar memutuskan litar apabila kilat berlaku.
[4 marks]

(b) Diagram 6.2 shows a system model for transmission of electrical power using
source of 12 V a.c.
Rajah 6.2 menunjukkan satu model sistem penghantaran kuasa elektrik
menggunakan sumber 12 V a.u.

Diagram 6.2
Rajah 6.2

Table 6.1 gives information on four types of cables that could be used for the
transmission of electricity over the National Grid Network.
Jadual 6.1 menunjukkan maklumat berkaitan empat jenis kabel yang boleh
digunakan untuk penghantaran elektrik melalui Rangkaian Grid Nasional.

AKADEMI SPM 2020 JPNT

MODUL 3 58 FIZIK SPM

Cable / Density / Rate of expansion Diameter / Specific heat
kabel / Kadar Diameter (cm)
ketumpatan capacity / Muatan
(kgm-3) pengembangan
haba tentu
(J kg-1 oC-1)

S 5.36 x 103 Low 2.0 502
T 2.00 x 103 Rendah 5.0 900
U 4.50 x 103 1.5 380
V 3.2 x 103 Low 3.2 790
Rendah

High
Tinggi
High
Tinggi

Table 6.1
Jadual 6.1

Explain the suitability of each of the characteristic of the cables. You are required to
choose the most suitable cable and give reasons for your choice.
Terangkan kesesuaian setiap satu ciri kabel. Anda dikehendaki memilih kabel yang
paling sesuai dan berikan sebab untuk pilihan anda.

[10 marks]

(c) In a model of transmission of electricity, 24 W of power is transmitted at potential
different of 48 V using cables with resistance of 4 Ω.

Dalam satu model penghantaran elektrik, kuasa 24 W dipindahkan pada beza
keupayaan 48 V menggunakan kabel dengan rintangan 4 Ω.

(i) Calculate the current in the cables.
Kirakan arus dalam kabel.

(ii) Calculate the power loss in the cable.
Kirakan kuasa yang hilang dalam kabel.

[5 marks]

AKADEMI SPM 2020 JPNT

MODUL 3 59 FIZIK SPM

7 Diagram 7.1 shows the structure of a cathode ray oscilloscope (CRO).
Rajah 7.1 menunjukkan struktur sebuah osiloskop sinar katod (OSK).

Diagram 7.1
Rajah 7.1

(a) State the process involved in producing electrons from electrode X.
Nyatakan proses yang terlibat dalam penghasilan elektron daripada elektrod X.

..…………………..…...........…………………………………....…………………..............
[1 mark]

(b) Describe the type of motion of the electron moving from Y to Z
Nyatakan jenis gerakan bagi elektron yang bergerak dari Y ke Z.

………………………..…………………………………………......………………..............
[1 mark]

(c) A student uses the CRO to study the output voltage from a signal generator.
Diagram 7.2 shows the trace displaced on the screen and the settings of the
CRO.
Seorang pelajar menggunakan OSK itu untuk mengkaji voltan output daripada
sebuah penjana isyarat.
Rajah 7.2 menunjukkan surih yang dihasilkan pada skrin dan pelarasan OSK itu.

Diagram 7.2 JPNT
Rajah 7.2

AKADEMI SPM 2020

MODUL 3 60 FIZIK SPM
[1 mark]
(i) Determine the peak voltage of the signal generator.
Tentukan voltan puncak bagi penjana isyarat itu.

(ii) Determine the frequency of the signal generator.
Tentukan frekuensi bagi penjana isyarat itu.

[2 marks]

(iii) Sketch the new trace in Diagram 7.3 if the time-base setting is now set at
0.01 s / div.
Lakarkan surih baru dalam Rajah7.3 jika dasar-masa ditetapkan pada
0.01 s / bhgn.

Diagram 7.3 [1 mark]
Rajah 7.3

8 Diagram 8.1 shows a deflecting cathode rays tube
Rajah 8.1 menunjukkan sebuah tiub pemesongan sinar katod.

Diagram 8.1
Rajah 8.1

AKADEMI SPM 2020 JPNT

MODUL 3 61 FIZIK SPM

(a) The function of the filament is to heat the cathode and releases electrons on its
surface
Fungsi filamen adalah untuk memanaskan katod bagi membebaskan elektron di
permukaannya .

(i) Name the process mention in (a)
Namakan proses yang dinyatakan dalam (a)

……………………….…..….………………………………………………………
[1 mark]

(ii) Why a very high voltage of is used in Diagram 8.1?
Mengapakah voltan yang sangat tinggi digunakan dalam Rajah 8.1?

…………………………………….………………………………………………….
[1 mark]

(iii) State the energy changes experience by the electrons from anode to the
screen.
Nyatakan perubahan tenaga yang berlaku pada elektron dari anod ke skrin

…………………..…………………………………………………………………..
[1 mark]

(b) Electrical potential energy 4.8 x 10-16 J gained by an electron is converted to kinetic
energy of the electron in the deflecting cathode rays tube
Calculate the velocity of the electron.
[The mass of an electron, m = 9.0 x 10-31 J]

Tenaga keupayaan elektrik 4.8 x 10-16 J yang diterima oleh satu elektron ditukarkan
kepada tenaga kinetik untuk elektron tersebut dalam tiub pemesongan sinar katod.
Hitung halaju elektron tersebut.
[Jisim bagi satu elektron, m =9.0 x 10-31 J]

[2 marks]

(c) (i) 1000 V power supply is connected to the top and lower plates. The top plate
is connected to the positive terminal and the lower plate is connected to the
negative terminal. Sketch the path of the cathode rays in Diagram 8.2.
1000 V bekalan kuasa disambungkan ke plat atas dan plat bawah. Plat atas
disambungkan ke terminal positif dan plat bawah disambungkan ke terminal
negatif. Lakarkan lintasan sinar katod di dalam Rajah 8.2.

AKADEMI SPM 2020 JPNT

MODUL 3 62 FIZIK SPM

Diagram 8.2
Rajah 8.2

[1 mark]

(ii) From your answer in (c)(i), state one characteristic of cathode rays.
Daripada jawapan anda dalam (c)(i), nyatakan satu sifat sinar katod.

..………………………………………………..…….……………………………………
[1 mark]

9 Diagram 9.1 shows an electronic system used to switch ON a security light outside a
house.
Rajah 9.1 menunjukkan satu sistem elektronik yang digunakan untuk menghidupkan
lampu keselamatan di luar rumah.

Diagram 9.1
Rajah 9.1

(a) Name the type of logic gate which received input A.
Namakan jenis get logik yang menerima input A.

..…………………………………………………………………………………….……….
[1 mark]

AKADEMI SPM 2020 JPNT

MODUL 3 63 FIZIK SPM

(b) Based on Diagram 9.1, complete the following sentences about input A, B and C
by tick [√ ] in the correct bracket.

Berdasarkan Rajah 9.1 lengkapkan ayat-ayat berikut mengenai input A, B dan C
dengan menandakan [√]dalam petak yang betul.

(i) If the surrounding is dark,
Jika persekitaran gelap

-input A will be ON OFF
-input A ialah PADAM

HIDUP

-so input B will be
-maka input B akan menjadi

ON OFF
HIDUP
PADAM
[2 marks]

(ii) If a person is detected ON OFF
Jika seseorang dikesan HIDUP PADAM

- input C will be
- input C akan menjadi

[1 mark]

(c) The security light should be switched on if a person is detected when it is dark.
Lampu keselamatan perlu dihidupkan sekiranya seseorang dikesan dalam
persekitaran yang gelap.

Name the type of logic gate which should be used in the box marked “Logic Gate X”
Namakan jenis get logik yang perlu digunakan dalam petak bertanda “Get Logik X”

..…………..………………………………..…………………………………………………..
[1 mark]

(d) Diagram 9.2 shows a combination of three logic gates.
Rajah 9.2 menunjukkan gabungan tiga get logik.

Diagram 9.2
Rajah 9.2

AKADEMI SPM 2020 JPNT

MODUL 3 64 FIZIK SPM

Construct a truth table for the gate combination shown in Diagram 9.2
Bina jadual kebenaran untuk gabungan get logik yang ditunjukkan pada Rajah 9.2

PQRS T

[2 marks]

10 As a research engineer in a factory, you are asked to investigate the characteristics of
several substances in order to produce semiconductors with better conductivity.

Sebagai jurutera penyelidik di sebuah kilang, kamu dikehendaki mengkaji ciri-ciri
beberapa bahan untuk menghasilkan semikonduktor yang mempunyai kekonduksian
yang tinggi.

(a) What is the meaning of semiconductor?
Apakah yang dimaksudkan dengan semikonduktor?

[1 mark]

Diagram 10.1 shows the bonding of silicon atoms, each with four valence electrons in
its outermost shell.
Rajah 10.1 menunjukkan ikatan atom-atom silikon, setiapnya dengan empat elektron
valens di petala luar.

Diagram 10.1
Rajah 10.1

(b) By using Diagram 10.1, explain how a n-type semiconductor is produced.
Dengan menggunakan Rajah 10.1, terangkan bagaimana semikonduktor jenis-n
dihasilkan.
[4 marks]

AKADEMI SPM 2020 JPNT

MODUL 3 65 FIZIK SPM

X T
M

Y 6V

N
1000 

Z

Diagram 10.2
Rajah 10.2

Diagram 10.2 shows a transistor circuit. Resistor M is a variable resistor and resistor N is
a fixed resistor. Bulb T will light up when the potential difference across N is at least 1 V.
Rajah 10.2 menunjukkan satu litar transistor. Perintang M adalah perintang boleh ubah
manakala perintang N adalah perintang tetap. Mentol T akan menyala apabila beza
keupayaan merentasi N adalah sekurang-kurangnya 1 V.

(c) When the potential difference between Y and Z is 1 V,
Apabila beza keupayaan antara Y dan Z adalah 1 V,

(i) What is the potential difference across X and Z? [1 mark]
Berapakah beza keupayaan merentasi X dan Z? [1 mark]

(ii) What is the potential difference across X and Y?
Berapakah beza keupayaan merentasi X dan Y?

(iii) Calculate the maximum resistance, M that enables the bulb T is light up.
Hitungkan rintangan maksimum, M untuk membolehkan mentol T itu
menyala.
[3 marks]

Diagram 10.3 shows four electronic circuits R, S, T and U with different specifications.
You are required to determine the most suitable electronic circuit to light up three street
lights 99 V, 69 W automatically with normal brightness when it is dark.

Rajah 10.3 menunjukkan empat litar elektronik R, S, T dan U dengan spesifikasi yang
berbeza. Anda dikehendaki menentukan litar elektronik yang paling sesuai untuk
menyalakan ketiga-tiga lampu jalan 99 V, 69 W secara automatik dengan kecerahan
normal apabila keadaan gelap.

AKADEMI SPM 2020 JPNT

MODUL 3 66 FIZIK SPM
Circuit Circuit diagrams
/ Litar Gambarajah litar. +
95 _V
R Relay

6V

S 6V
T
AKADEMI SPM 2020 Relay +
6V 95_V

JPNT

MODUL 3 67 FIZIK SPM
U Relay
+
6V 95 _V

Diagram 10.3
Rajah 10.3

Study the specifications of all of the four circuits based on the following aspects:
Kaji semua spesifikasi tersebut berdasarkan aspek-aspek berikut:

‐ The position of the light dependent resistor (LDR).
Kedudukan perintang peka cahaya (PPC).

‐ The connection of the batteries.
Penyambungan bateri.

‐ The arrangement of the street lights circuit.
Susunan litar lampu-lampu jalan

‐ The use of a relay switch in the circuit.
Penggunaan suis geganti dalam litar.

Determine the most suitable circuit diagram to be chosen and give reasons for your
choice.
Tentukan gambarajah litar yang paling sesuai dipilih dan berikan sebab bagi pilihan
anda.

[10 marks]

AKADEMI SPM 2020 JPNT

MODUL 3 68 FIZIK SPM

11 Diagram 11.1 shows the rate of decay of radioactives K and L respectively. The rates
sources for radioactive K and L were placed in front of a detector and the count
were recorded every two minutes.

Rajah 11.1 menunjukkan kadar penyusutan radioaktif K dan L. Sumber radioaktif K dan
L diletakkan di hadapan satu alat pengesan dan kadar bilangan direkodkan setiap dua
minit.

Diagram 11.1
Rajah 11.1

(a) Name the suitable detector to be used.
Namakan alat pengesan yang sesuai untuk digunakan.

.....................…………………………………………………………………………………..
[1 mark]

(b) Based on Diagram 11.1;
Berdasarkan Rajah 11.1;
(i) Which source has a longer half-life?
Sumber yang manakah mempunyai separuh hayat yang lebih panjang?

……..……………………………………………………………………………………..
[1 mark]

(ii) Show on the graph how the half-life in 11(b) (i) is determined.
Tunjukkan di atas graf bagaimana separuh hayat dalam 11(b)(i) ditentukan.
[1 mark]

(c) Calculate the rate of decay of K that has decayed after 20 minutes.
Hitungkan kadar pereputan K yang telah mereput selepas 20 minit.

AKADEMI SPM 2020 [2 marks]
JPNT

MODUL 3 69 FIZIK SPM

(d) Diagram 11.2 shows a system used to detect cracks in concrete walls.
Rajah 11.2 menunjukkan satu sistem yang digunakan untuk mengesan rekahan
dinding konkrit.

Diagram 11.2
Rajah 11.2

Table 11 shows four radioisotopes with their respective properties.
Jadual 11 menunjukkan empat radioisotop dengan ciri masing-masing.

Radioisotopes Type of radiation Half Life Physical state
radioisotop Jenis sinaran Separuh hayat Keadaan fizikal

Iridium-192 Gamma 74 days Solid
Gama 74 hari Pepejal

Caesium-137 Gamma 31 days Liquid
Iodine-131 Gama 31 hari Cecair
Nitrogen-16
Beta 8 days Solid
Beta 8 hari Pepejal

Beta 14 days Liquid
Beta 14 hari Cecair

Table 11
Jadual 11

Based on the Table 11, state the suitable characteristics of the radioisotopes
used to detect the crack in the concrete wall. Give reasons for your choice.
Berdasarkan jadual, nyatakan ciri-ciri radioisotop yang sesuai digunakan
untuk mengesan rekahan dalam dinding konkrit. Beri sebab bagi pilihan anda.

AKADEMI SPM 2020 JPNT

MODUL 3 70 FIZIK SPM

(i) Type of radiation
Jenis sinaran

…………….……………………………………………………………..………………..
Reason
Sebab

...…………………………………………………………………………………………..
[2 marks]

(ii) Half-life
Separuh Hayat

……………………...……………………………………………………………………..
Reason
Sebab

...…………………………………………………………………………………………..
[2 marks]

(iii) Physical state
Keadaan fizikal

..……………………….…………………………………………………………………..
Reason
Sebab

………………..…………………………….……………………………………………..
[2 marks]

(e) Determine the most suitable radioisotope that can be used to detect the crack in the
concrete wall.
Tentukan radioisotope yang paling sesuai digunakan untuk mengesan rekahan
dalam dinding konkrit.

………………………………………………………………………………………………….
[1 mark]

AKADEMI SPM 2020 JPNT

MODUL 3 71 FIZIK SPM

12 Diagram 12 shows a system used in a factory to ensure the thickness of a cardboard
sheet is uniform.
Rajah 12 menunjukkan satu sistem yang digunakan di sebuah kilang untuk memastikan
ketebalan kepingan kadbod adalah seragam.

Diagram 12
Rajah 12

The radioactive source, radiation detector and counter are used to detect the thickness
of the cardboard sheet. The radioactive source contains a radioisotope. The roller is
used to compress the cardboard sheet.
Sumber radioisotop, pengesan sinaran dan pembilang digunakan untuk mengesan
ketebalan kepingan kadbod. Sumber radioaktif itu mengandungi radioisotop. Penggelek
digunakan untuk memampatkan kepingan kadbod.

Table 12 shows four radioisotope with their respective properties.
Jadual 12 menunjukkan empat radioisotop dengan sifat masing-masing.

Radioisotope. Half-life. Type of ray. Physical state.
Radioisotop. Setengah-hayat. Jenis sinaran. Keadaan fizikal

Sodium-24 (Na) 15 hours Gamma Liquid
Natrium-24 (Na) 15 jam Gama cecair

Phosphorus-32(P) 14.3 days Beta Liquid
Fosforus-32 (P ) 14.3 hari Beta cecair

Cobalt-60(Co) 5.27 years Beta Solid
Kobalt-60 (Co) 5.27 tahun Beta pepejal

Strontium-90(Sr) 28.5 years Gamma Solid
Strontium-90(Sr) 28.5 tahun Gama pepejal

Table 12
Jadual 12

(a) What is meant by radioisotope?
Apakah yang dimaksudkan dengan radioisotop?

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

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

AKADEMI SPM 2020 JPNT

MODUL 3 72 FIZIK SPM

(b) Based on the Table 12, state the suitable radioisotope that can be used to detect the
thickness of the cardboard sheet . Give reason for the suitability of the properties.
Berdasarkan Jadual 12, nyatakan sifat-sifat radioisotop yang boleh digunakan
untuk mengesan ketebalan kepingan kadboard. Beri sebab mengapa sifat-sifat itu
sesuai.

(i) Half-life.
Separuh-hayat.

...………………………………………………………………………………………….
Reason.
Sebab.

…………………………………………………………………………………………….
[2 marks]

(ii) Type of radiation.
Jenis sinaran.

....………………………………………………………………………………………….
Reason
Sebab.
.....................…………………………….……………………………………………….

[2 marks]

(iii) Physical state.
Keadaan fizikal.

...……………………………….………………………………………………………….
Reason.
Sebab.

...…………………………….…………………………………………………………….
[2 marks]

(c) Based on the answers in 12(b), determine the most suitable radioisotope in Table 12
to detect the thickness of the cardboard sheet.
Berdasarkan jawapan di 12(b), tentukan radioisotop dalam Jadual 8 yang paling
sesuai digunakan untuk mengesan ketebalan kepingan kadbod.

......…………………………….……………………………………………………………….
[1 mark]

AKADEMI SPM 2020 JPNT

MODUL 3 73 FIZIK SPM

(d) The radioisotope in 12(c) is used to detect the thickness of the cardboard sheet.
Radioisotop di 12(c) digunakan untuk mengesan ketebalan kepingan kadbod.

State the change in the reading of the counter when a thicker cardboard is used.
Nyatakan perubahan bacaan pembilang apabila kadbod yang lebih tebal digunakan.

……………………………………………………...………………………………………….
[1 mark]

(e) How is the thickness of the cardboard sheet reduced?
Bagaimanakah ketebalan kadbod dikurangkan?

...……………………………………………………………………………………………….
[1 mark]

(f) The half-life of Cobalt-60 is 5.27 years.
Separuh hayat Kobalt-60 ialah 5.27 tahun.

Calculate the time taken for the activity of Cobalt-60 to reduce to 12.5 % of its initial
value.
Hitungkan masa yang diambil untuk keaktifan Kobalt-60 berkurang menjadi 12.5%
daripada nilai asalnya.

[2 marks]

13 Rajah 13(a) menunjukkan persamaan satu tindakbalas nuklear.

235 U + 01n → 141 Cs + 93 Rb +2 01n + tenaga
92 55 37

Rajah 13(a)

Cacat jisim yang dihasilkan dalam tindakbalas di atas adalah 0.19585 u.
[1 u = 1.66 x 10 -27 kg]

AKADEMI SPM 2020 JPNT

MODUL 3 74 FIZIK SPM

(a) Lengkapkan ayat berikut dengan menandakan ( √ ) kotak yang betul.
Persamaan di atas menunjukkan tindakbalas
pembelahan nukleus
pe pelakuran nukleus
[1 markah]

(b) Berdasarkan persamaan tindakbalas dalam Rajah 13(a), hitung
(i) tenaga yang dibebaskan.

[2 markah]

(ii) kuasa yang dijanakan dalam masa 5 µs.

[2 markah]

AKADEMI SPM 2020 JPNT

MODUL 3 75 FIZIK SPM

(c) Rajah 13(b) menunjukkan sebuah reaktor nuklear yang digunakan untuk menjana
tenaga nuklear.

Rajah 13(b)

Anda dikehendaki menyiasat ciri-ciri bahagian dalam reaktor nuklear seperti
yang ditunjukkan dalam Jadual 13.

Reaktor Bahan untuk Bahan untuk rod Ketebalan
nuklear moderator
pengawal perisai konkrit

J Grafit Kripton Nipis

K Besi Boron Nipis

L Grafit Boron Tebal

M Besi Kripton Tebal

Jadual 8

Berdasarkan maklumat dalam Rajah 13 dan Jadual 13, nyatakan ciri-ciri reaktor
nukleur yang dapat meghasilkan tenaga dalam keadaan selamat dan terkawal.
Beri sebab bagi kesesuaian ciri-ciri tersebut.

(i) Bahan untuk moderator

.………………………………………………………………………….......................
[1 markah]

Sebab

.………………………………………………………………………….......................
[1 markah]

AKADEMI SPM 2020 JPNT

MODUL 3 76 FIZIK SPM

(ii) Bahan untuk rod pengawal

………………………………………………………………………….......................
[1 markah]

Sebab

………………………………………………………………………….......................
[1 markah]

(iii) Ketebalan perisai konkrit

………………………………………………………………………….......................
[1 markah]

Sebab

………………………………………………………………………….......................
[1 markah]

(d) Berdasarkan jawapan di 13 (c), tentukan reaktor nukleur dalam Jadual 13 yang
dapat menghasilkan tenaga dalam keadaan selamat dan terkawal.

……………………………………………………………………....................................
[1 markah]

14 (a) Diagram 14.1 shows a a water pipe that is located under a concrete layer. Water is
leak out from the crack on the water pipe.
Rajah 14.1 menunjukkan sebatang paip air yang tereletak di bawah lapisan konkrit.
Air meleleh keluar dari rekahan pada paip air itu.

Diagram 14.1
Rajah 14.1

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MODUL 3 77 FIZIK SPM
[1 mark]
Radioisotope is used to detect the crack on the water pipe.
Radioisotop digunakan bagi mengesan rekahan pada paip air itu.

(i) What is radioisotope?
Apa itu radioisotop?

(ii) Explain how the radioisotope is used to detect the crack on the water pipe.
Terangkan cara radioisotop digunakan untuk mengesan rekahan pada paip air
itu.
[4 marks]

(b) Diagram 14.2 shows a nuclear fission and equation for the reaction.
Rajah 14.2 menunjukkan pembelahan nukleus dan persamaan tindak balas
tersebut.

Diagram 14.2
Rajah 14.2

Table 14.1 shows the atomic mass unit(u) of the radioactive elements involved in
the fission reaction.
Jadual 14.1 menunjukkan unit jisim atom(u) unsur radioaktif yang terbabit dalam
tindak balas nuklear.

Radioactive element Atomic mass unit (u)
Unsur radioaktif Unit jisim atom (u)
Uranium, U-235 235.04392
Krypton, Kr 91.92611
Barium, Ba 140.91441
Neutron, n 1.00867

Table 14.1
Jadual 14.1

AKADEMI SPM 2020 JPNT

MODUL 3 78 FIZIK SPM

Calculate / Hitung:
(i) the mass defect in kilogram

cacat jisim dalam kilogram
[ 1 u = 1.66 x 10-27 kg]

(ii) the energy produced in the fission reaction.
tenaga yang terhasil dalam tindak balas pembelahan itu.
[ 5 marks]

(c) Diagram 14.3 shows a cross section of a nuclear reactor model.
Rajah 14.3 menunjukkan keratan rentas bagi model reaktor nuklear.

Diagram 14.3
Rajah 14.3

A new nuclear reactor is to be built on an island.
Table 14.2 shows the characteristics of four nuclear reactor models, J, K, L and M
with different specifications.
Sebuah reaktor nuklear baharu akan dibina di atas sebuah pulau.
Jadual 14.2 menunjukkan ciri empat model reaktor nuclear, J, K, L dan M dengan
spesifikasi yang berbeza.

Reactor Fuel Physical state of Half-life of Control rod
Reaktor Bahan api the fuel the fuel Rod
Keadaan fizikal Setengah pengawal
J Uranium bahan api hayat bahan
Uranium api Cadmium
Solid Long Kadmium
K Krypton Pepejal Panjang Graphite
Kripton Liquid Short Grafit
Cecair Pendek Cadmium
L Uranium Liquid Short Kadmium
Uranium Cecair Pendek Graphite
Solid Long Grafit
M Krypton Pepejal Panjang
Kripton Table 14.2
Jadual 14.2

Determine the most suitable nuclear reactor model that can function efficiently.
Justify your answer.
Tentukan model reaktor nuklear yang paling sesuai yang boleh berfungsi dengan
cekap.
Justifikasikan jawapan anda.

[10 marks]

AKADEMI SPM 2020 JPNT

MODUL 3 79 FIZIK SPM

Cadangan jawapan MODUL 3
Soalan 1
(a) Temporary magnet
(b)

(c) (i) Diagram 1.2 > Diagram 1.1
Diagram 1.2 > Diagram 1.1
Same

(d) If the number of turns increase, the strength of the magnetic field increase.
(e) Increase

Concentrate the magnetic fluxs.

Soalan 2

(a) 3 correct 2 marks
2 correct 1 marks
1 correct 0 marks

(b) (i) Y to X
(ii)

F
(iii) Increase
(c)

1st : correct pattern JPNT
2nd : direction of magnetic lines and catapult force correct.
(d) Reverse the magnetic poles / current flow

AKADEMI SPM 2020

MODUL 3 80 FIZIK SPM

Soalan 3

(a) (i) To switch on a high current/voltage circuit

(ii) the relay coil become electromagnet
The soft iron amarture is pulled to the relay coil
The relay contact is connected.

(b) Soft iron rod

(c) increase the number of turns of the relay coil.
Increase the diameter of the wire in the relay coil.

NO. ITEM MARKAH
SOALAN 1
4(a) (i) Electromagnetic induction is the production of induced emf
/current in a conductor when there is a change/ cutting of 1
(ii) magnetic flux/field across it
Aruhan electromagnet ialah penghasilan beza upaya dalam
suatu konduktor apabila terdapat perubahan fluks magnet
melalui konduktor itu
Faraday’s Law states that the magnitude of the induced emf
/current is directly proportional to the rate of change of magnetic
flux.
Hukum Faraday menyatakan magnitude dge aruhan adalah
berkadar terus dengan kadar perubahan fluks magnet

(b) (i) 1.The magnetic field is being cut by the coil / Magnetic flux 1

change takes place / A current is induced in the coil.

Medan magnet dipotong oleh gegelung/ Perubahan fluks

magnet berlaku / Arus diaruhkan dalam gegelung.

2.The pointer of the sensitive galvanometer deflect to the left

and to the right continuously.

Petunjuk galvanometer peka itu akan dipesongkan ke kiri dan 1

kekanan secara berterusan

(ii) End P becomes a North pole 1

Hujung P menjadi kutub utara

(iii) Lenz Law 1

Hukum Lenz

(c) (i) Converted to electrical/ heat energy in the coil 1

Ditukar kepada tenaga haba/elektrik dalam gegelung

(ii) 1. Increase the number of turns in the coil 2

Menambahkan bilangan lilitan dalam gegelung (Any

2. Use a thicker wire for the coil 2)

Gunakan dawai lebih tebal bagi gegelung

3. use stronger permanent magnet

Gunakan magnet kekal yag lebih kuat

AKADEMI SPM 2020 JPNT

MODUL 3 81 FIZIK SPM
1
4. increase the speed of oscillation of permanent magnet
Menambah kelajuan ayunan magnet kekal

(d) Generator / Dynamo
Penjana elektrik/ dinamo

NO. ITEM MARKAH
SOALAN
5(a) Transformer injak turun 1
(b) Easy magnetised and demagnetised 1
(c) Ns = Vs
Np Vp

Ns = 12 x 3000
240

= 150
(d) (i) Bulb does not light up

(ii) No current is induced in secondary coil/ No change in magnetic
flux.

NO. MARK ITEM NOTE
QUESTION 1
An electromagnet is a solenoid which can Any 4
6 (a)(i) 1 produce magnetic field when current passes answers.
1 through it // Electromagnet is a device in which
(a)(ii) 1 magnetism is produced by an electric current
1 // temporary magnet made by winding a coil
1 round a soft iron core and magnetic field
produce when current flow.
Max: 4  During lightning current gets too high.
marks  Magnetic field becomes stronger
 The electromagnet pulls the soft iron armature
 Release the catch
 The contacts are separated and the current

stopped.

AKADEMI SPM 2020 JPNT

MODUL 3 82 FIZIK SPM
(b)
Characteristics Reason
(c)(i)
(c)(ii) 1,1 Density must be low The cable will be
TOTAL
MARK lighter

1,1 Rate of expansion must Cable do not expand
be low easily

1,1 Diameter of the cable Reducing resistance
must be bigger //

thicker

1,1 Specific heat capacity the temperature do not

must be high increase fast

I choose T
1 Explanation because it has low
1 density, low rate of

expansion, high

diameter and high

specific heat capacity.

P = IV
1 24 W = (I) (48 V)
1 I = 0.5 A
1 P = I2R
1 P = (0.5)2 x 4Ω
1 P=1W

20

No Answer Marks Total
7 (a) Thermionic emission 1
1
(b) Uniform acceleration 1
1
(c) (i) VP = 4 V
(ii) T = 3 x 0.02 = 0.06 s 1
f = 16.7 Hz

(iii) Sinusoidal with one complete cycle

AKADEMI SPM 2020 JPNT

MODUL 3 83 FIZIK SPM

Total 6
1
8 (a) (i) Thermionic emission 1
(ii) To accelerate the electrons 1
(iii) Kinetic energy to heat and light 1
(b) 4.8 x 10 -16 = ½ x 9.0 x 10 -31 x v 2 1
3.27 x 10 7 ms-1 1
(c) (i) 1
7
(ii) Deflect in electric field // negatively charge
TOTAL JPNT

9
(a) NOT gate
(b) (i) Input A - off

Input B - on
(ii) on
(c) AND gate
(d)

PQRS T
00001
01011
10101
11110

AKADEMI SPM 2020

MODUL 3 84 FIZIK SPM

10
(a) Semiconductor is a material with electrical conductivity better than insulator but weaker

than a conductor
(b) Doping process/Silicon is doped with pentavalent atoms/Phosphorus/Antimony

To produce covalent bond
Increase the free electron inside the semiconductor
Majority charge-carriers is negative electron

Si Si Si Si


Si P Si Si

Free
 electron
Si Si P Si

(c) (i) V X-Z = 6 V
(ii) V X-Y = 6 -1 = 5 V

(iii) VM   RM   6V
RM  RN

5   RM RM   6V
 1000

9RM+ 9000 = 6RM
RM= 9000 Ω

(d) LDR is connected at base circuit
When intensity of light is low / dark, resistance of LDR
increases / so Vbase is large / transistor switched on
Terminal positive of batteries is connected to collector
So that the transistor is forward biased
Bulbs are arranged in parallel circuit
All bulbs are connected to voltage supply of 99V
Relay switch is used
So that the secondary circuit will switch on // So that the
electromagnet will switch on the secondary circuit
Choose A
Because LDR is connected at base circuit, terminal positive of batteries is connected to
collector; bulbs are arranged in parallel circuit and relay switch is used.

11. JPNT
(a) Name the suitable detector used correctly GM Tube

AKADEMI SPM 2020

MODUL 3 85 FIZIK SPM

(b) (i) Choose source of longer half life correctly K
(ii) Show on the graph correctly 4 minutes

(c) Calculate the rate decay of K after 20 minutes correctly.
5T1/2
6.25
200 100 50 25 12.5 6.25

(d) (i) State the suitable characteristics and give reason correctly
Gamma
High penetrating power

(ii) Long half-life
Long lasting // can be used for a longer time

(iii) Solid
Easy to handle // does not spill // easy to contain

(e) Determine the most suitable radioisotope to detect crack in the concrete wall
correctly
Iridium – 192

12
(a) radioisotope is an unstable nucleus that emits radiation(decay) to become more
stable
(b) (i) Has long half life
to save cost
(ii) Beta particle
has penetrating power that is enough to penetrate the cardboard
sheet. Therefore,
over expose will not occur
(iii) solid
can be handled easily
kobalt – 60

(c) Decrease

(d) When the sheet is too thick, the detector will receive lower counts. As a result,
the computer will make proper adjustment to make the roller to increase

compression on the sheet

(e) 100 % 50% 25% 12.5%

(f) Time taken = 3 half-life = 3 x 5.27 years = 15.81 years.

13 JPNT
(a) Pembelahan nukleus
(b) (i) E = mc2
= 0.19585 x (1.66 x 10-27 ) x (3 x 10 8 ) 2
= 2.9260 x 10 -11 J

(ii) P = E
t

= 2.92599 x 10 -11

AKADEMI SPM 2020

MODUL 3 86 FIZIK SPM

5 x 10 -6

= 5.8520 x 10 -10 W
(c) (i) -grafit

-memperlahankan halaju gerakan neutron
(ii) -rod boron

-menyerap sebahagian neutron untuk memperlahankan kadar tindakbalas
(iii) -ketebalan tinggi / tebal

-untuk mengelakkan kebocoran sinaran radioaktif ke persekitaran.
(d) Reaktor nukleur L

14.

(a) (i) Isotope unstable//isotop tidak stabil
(ii) 236.05259 – 235.86653

0.18606
0.18606 × 1.66 × 10-27 // 3.088596 × 10-28

3.088596 × 10-28 × (3 × 108)2
2.7797 × 10-11 J

(c)

Uranium Unstable // large nucleon

number // large proton

number //tidak stabil //

nombor proton besar //

number jisim besar

Solid // pepejal Easy handle // mudah

kendali // easy store //

mudah simpan // not spill

// tidak tumpah

Long half life // setengah Use long // long lasting //

hayat lama guna lama // tahan lama //

lasting // do not need to

replace often // tidak perlu

ganti kerap

Cadmium// kadmium Absorp neutron // control

energy @ chain @ fission

// serap neutron //kawal

tindak balas rantai

J Kombinasi markah

AKADEMI SPM 2020 JPNT