07 Modul SC T2-Bab7(csy4p)

Perbezaan cas menarik Fenomena (Cas Elektrostatik) Litar Bersiri / Series Circuit
Different charge attract Phenomena (Electrostatic Charge)
Sel kering +–
–+ • Kejadian kilat / Lightning Dry cell
Cas sama menolak • Palam pencucuh Mentol + –
Same charge repel Spark plug Bulb
+ +– – • Pakaian nilon
Nylon clothes Litar + P–arallel Circuit
Garisan medan magnet mengarah • Menyikat rambut
dari kutub Utara ke kutub Selatan Comb hair Selari /
The magnetic field lines begin from • Pemetik api elektronik
the North pole to the South pole Electronic lighter +–

7 BAB

CHAPTER

Keelektrikan
dan

Kemagnetan

Electricity and
Magnetism
SAINS TINGKATAN 2Komponen Elektrik
Electrical Components
Bab
Kutub sama – menolak, ChapterMagnetArah medan magnet dapatKomponenSimbolKomponen Simbol
Kutub berlainan – menarik Magnet ditentukan menggunakan Component Symbol Component Symbol
Similar poles – repel, 7petua genggaman tanganSel kering Perintang
Different poles – attract95 © Nilam Publication Sdn. Bhd.kanan / The direction V G
of magnetic field can be Dry cell A Resistor or / atau
determined using the right- Suis Fius
hand grip rule Switch Fuse

Berkutub – Utara dan Selatan Menarik bahan magnet Voltmeter Galvanometer
Has Poles – North and South Attracts magnetic materials Voltmeter Galvanometer
Ammeter
Ammeter Perintang boleh
Mentol lampu ubah

Bulb Rheostat
(variable resistor)

SAINS TINGKATAN 2

7.1  Keelektrikan / Electricity

7.1.1 K.Kejayaan / S.Criteria

7.1.2 Menghuraikan dan berkomunikasi mengenai tenaga. / Describe and communicate about energy.

7.1.3 Menerangkan dan berkomunikasi mengenai kewujudan cas elektrostatik.
SP Explain and communicate the existence of electrostatic charges.
LS 7.1.4
Menjelaskan dengan contoh elektrostatik dalam kehidupan seharian. / Explain with examples electrostatic in daily life.
7.1.5
Merumuskan cas yang mengalir menghasilkan arus elektrik.
7.1.6 Draw a conclusion that the flow of charges produces electric current.

EMK Mencirikan arus, voltan dan rintangan serta unitnya. / Characterise current, voltage and resistance, and their units.
Nilai Murni
Moral Value Merumuskan perkaitan antara arus, voltan dan rintangan.
Draw a conclusion on the relationship between current, voltage, and resistance.

Kemahiran saintifik (proses pemikiran dan kemahiran manipulatif tertentu) / Scientific skills (specific processes of thinking and manipulative skills)

Jujur dan tepat dalam merekod dan mengesahkan data
Honest and accurate in recording and verifying data

Tenaga Buku Teks muka surat 142
Energy Textbook page 142

1 Tenaga ialah kebolehan untuk melakukan kerja . Unit S.I. bagi tenaga ialah joule (J) .
.  TP1
Energy is the ability to carry out work . The S.I. for energy is joule (J)

2 Tenaga boleh ditemui dalam pelbagai bentuk.
Energy can be found in different forms.  TP1 TP2

Jenis tenaga Maksud Contoh
Types of energy Meaning Example

Tenaga Tenaga yang disimpan dalam suatu objek disebabkan
keupayaan elastik kedudukan dan keadaannya .
Elastical Energy stored in an object due to its position and condition.
potential energy

Tenaga
keupayaan graviti
Gravitational
potential energy

Tenaga kinetik Tenaga yang dimiliki oleh suatu objek yang sedang
Bab Kinetic energy bergerak .
Chapter

7 Energy possessed by a moving object.

Tenaga haba Suatu bentuk tenaga dalam suatu objek yang
Heat energy panas
Tenaga cahaya .
Light energy
A form of energy in a hot object.

Tenaga yang membolehkan kita melihat .
The energy which enables us to see .

© Nilam Publication Sdn. Bhd. 96

Jenis tenaga Maksud SAINS TINGKATAN 2
Types of energy Meaning
Tenaga bunyi Contoh
Sound energy Example

Tenaga yang dihasilkan oleh objek yang bergetar .
object.
The energy produced by vibrating

Tenaga elektrik Tenaga yang dihasilkan oleh aliran elektron .
Electrical energy The energy produced by the flow of electron .

Tenaga kimia Tenaga yang tersimpan dalam suatu bahan .
Chemical energy .
The energy stored in a substance

Tenaga nuklear Dibebaskan daripada tindak balas pembelahan atau
Nuclear energy pelakuran yang berlaku dalam nukleus

atom.

It is released from fission or fusion reactions which

occur in atomic nucleus .

3 Sumber tenaga. / Sources of energy.  TP1

Matahari Ombak
Sun Waves

Angin Sumber Geoterma Bab
Wind tenaga Geothermal Chapter
Energy
Biojisim sources Water 7
Biomass Air

Bahan api fosil Bahan radioaktif
Fossil fuel Radioactive
substances

97 © Nilam Publication Sdn. Bhd.

SAINS TINGKATAN 2

Cas Elektrostatik Buku Teks muka surat 144
Electrostatic Charge Textbook page 144

1 Elektrostatik adalah kajian cas elektrik statik iaitu cas-cas yang pegun .

Electrostatic is a study of static electrical charges, that is charges which are stationary .  TP1

2 Cas elektrik statik boleh dihasilkan melalui geseran .

Static electrical charges are produced in friction .  TP1

(a) Semua atom terdiri daripada proton (bercas positif ) dan elektron (bercas negatif ).
charges).  TP1
All atoms are made up of proton ( positive charges) and electron ( negative

(b) Apabila geseran berlaku antara dua jenis atom yang berlainan, elektron boleh berpindah dari satu jenis
atom ke satu jenis atom yang lain seperti dalam rajah berikut.

When friction happens between two different types of atoms, electrons can transfer from one type of

atom to another type of atom as shown in the following diagram.  TP2

Elektron Elektron dipindahkan
Electron Electron is transferred

Proton
Proton

Atom A Atom B
Atom A Atom B

(i) Atom A bercas positif kerana bilangan elektron di dalamnya menjadi kurang ; manakala Atom B
bercas negatif kerana bilangan elektron di dalamnya bertambah . ; whereas Atom B is

Bab Atom A is positively charged because the amount of electron in it has reduced
Chapter
negatively charged because the amount of electron in it has increased .
7

(ii) Bahan neutral mempunyai jumlah cas positif (proton) dan cas negatif (elektron) yang sama.
object contains same amount of positive charges (protons) and negative charges
A neutral

(electrons).

© Nilam Publication Sdn. Bhd. 98

SAINS TINGKATAN 2

3 Untuk mengesan cas elektrostatik yang kecil, elektroskop digunakan.
To detect small electrostatic charges, an electroscope is used.  TP4

Langkah Pemerhatian Penerangan
Step Observation Explanation

Sebatang pembaris plastik Elektroskop Ceper logam Pembaris plastik neutral .
dibawa mendekati ceper Electroscope Metal cap The plastic ruler is neutral .
logam elektroskop. Kerajang emas
A plastic ruler is brought Gold leaf
near the metal cap of an
electroscope.

Tiada perubahan pada kerajang

emas .

No change at the gold leaf .

Sebatang pembaris plastik Pembaris digosok dengan Pembaris plastik bercas .
dibawa mendekati ceper kain bulu / Ruler rubbed The plastic ruler has charge .
logam elektroskop setelah with woollen cloth
digosok dengan kain bulu.
A plastic ruler which Elektroskop Ceper logam
has been rubbed with a Electroscope Metal cap
woollen cloth is brought Kerajang emas
near the metal cap of an Gold leaf
electroscope.
Kerajang emas mencapah .
The gold leaves diverge .

4 Terangkan langkah-langkah keselamatan dalam pengendalian cas elektrostatik dengan mengisi tempat kosong
dengan perkataan yang diberi.

Explain the following safety masures in handling electrostatics charges by filling in the blanks with the words
provided.  TP3

rantai logam dinyahcas konduktor kilat roda Bab
metal chains discharged lightning conductors wheels Chapter

7

(a) Bangunan-bangunan yang tinggi dilengkapi dengan

konduktor kilat yang menghantar kilat ke bumi secara
langsung.

Tall buildings are equipped with lightning conductors that send
lightning to the earth directly.

99 © Nilam Publication Sdn. Bhd.

SAINS TINGKATAN 2

(b) Kapal terbang perlu dinyahcas sebelum mendarat. Ini dilakukan

dengan mengumpulkan cas-cas pada bahagian roda . Cas-
cas melompat ke bumi apabila kapal terbang mendekati permukaan
darat semasa mendarat.

An aeroplane needs to be discharged before landing. This is done

by accumulating charges at the wheels . Charges jump to the

earth when the aeroplane is near to the earth when landing.

(c) Lori minyak yang membawa minyak dan bahan-bahan mudah
terbakar mempunyai satu rantai logam yang menyentuh lantai
untuk menyahcas.

An oil tanker that carries oil and flammable substances has a
metal chain that touches the earth to discharge.

Aktiviti 7.1 Kewujudan Cas Elektrostatik
Activity The Existence of Electrostatic Charge

Tujuan Mengkaji kewujudan cas elektrostatik pada bahan.
Aim To study the existence of electrostatic charge.

Bahan Belon, cebisan kecil kertas
Materials Balloon, small pieces of paper

Radas Rod politena, jalur selulosa asetat, kain bulu
Apparatus Polythene rod, cellulose acetate strip, wool cloth

Prosedur 1 Gosok rod politena dengan kain bulu. Rod politena
Procedure Rub the polythene rod with wool cloth. Polythene rod

2 Dekatkan rod itu pada cebisan kertas kecil.
Bring the rod over a small piece of paper.
3 Ulang langkah 1. / Repeat step 1.
Bab 4 Dekatkan rod itu dengan aliran air paip yang halus Cebisan kertas
Pieces of paper
Chapter dan rekodkan pemerhatian anda.
Bring the rod near to a small flow of tap water and record your observation.
7

5 Ulang langkah 1 hingga 4 dengan jalur selulosa asetat dan belon menggantikan rod politena.
Repeat steps 1 to 4 with cellulose acetate strip and balloon to replace the polythene rod.

Pemerhatian Bahan Cebisan kertas Aliran air paip
Observations Materials Pieces of paper Flow of water tap
Rod politena Menarik kertas Aliran air membengkok
Polythene rods
Jalur selulosa Attract paper Water flow bent
Celulose acetate strip Menarik kertas Aliran air membengkok

Belon Attract paper Water flow bent
Balloon Menarik kertas Aliran air membengkok

Attract paper Water flow bent

Kesimpulan C as elektrostatik wujud pada suatu bahan.
Conclusion Electrostatic charge exist on an object.

© Nilam Publication Sdn. Bhd. 100

Projek / Project SAINS TINGKATAN 2

  Arahan / Instructions: PdPc
Jalankan simulasi kejadian kilat dengan menggunakan penjana Van de Graaff. 21
Conduct a simulation of lightning by using Van de Graaff generator.  TP2
1 Hidupkan penjana Van de Graaff.
Switch on Van de Graaff generator.
2 Selepas beberapa minit, dekatkan sfera logam pada kubah.
After a few minutes, bring the metal sphere near to the dome.
3 Perhatikan apa yang berlaku dan bincangkan di dalam kelas.
Observe what happens and discuss it in the class.

Projek / Project

  Arahan / Instructions: PdPc
Secara berkumpulan, kaji situasi berikut: 21
In group, study the following situations:

(a) Pemilihan jenis fabrik yang sesuai dipakai ketika cuaca panas
Choosing type of fabric that suitable to wear during hot weather

(b) Kawasan perlindungan yang selamat semasa ribut petir (konsep Faraday’s Cage’)
Safe protection area during thunder storm (Faraday’s Cage)

Bincangkan cara penyelesaian situasi tersebut berdasarkan konsep elektrostatik. Bentangkan hasil perbincangan
dalam kelas.
Discuss ways to solve these situations based on electrostatic concept. Present the findings of the discusssion in
class.  TP6

Arus Elektrik Buku Teks muka surat 148 Bab
Electric Current Textbook page 148 Chapter

7

1 Beri definisi istilah-istilah berikut dengan mengisi tempat kosong.
Define the following terms by filling in the blanks.  TP1

(a) Tenaga elektrik – tenaga yang dihasilkan apabila cas-cas mengalir dalam satu arah

Electrical energy – energy that is produced when charges flow in one direction

(b) Arus elektrik – kadar pengaliran cas elektrik

Electric current – the rate of flow of electrical charges

(c) Voltan – daya elektrik yang diperlukan untuk menggerakkan cas dari satu titik ke titik lain

dalam satu litar lengkap

Voltage – electrical force that is needed to move charges from one point to another in a complete circuit

(d) Rintangan – faktor-faktor dalam konduktor yang mengurangkan jumlah arus

Resistance – factors in a conductor that reduce the amount of current

101 © Nilam Publication Sdn. Bhd.

SAINS TINGKATAN 2

2 Cas-cas statik dihasilkan apabila sesuatu objek menggosok objek yang lain. Cas-cas yang dihasilkan dengan cara ini

adalah pegun. Malah jika cas-cas yang pegun ini mengalir dari satu tempat ke tempat lain, arus elektrik

dihasilkan. / Static charges are produced when an object rubs against another object. Charged produced in this way

are stationary. However, if these stationary charges flow from one place to another, electric current is
produced.  TP2

3 Untuk memerhatikan aliran arus elektrik, sebuah penjana Van de Graaff dicaskan dan disambungkan dengan
pili air seperti berikut. / To observe the flow of electrical current, a Van de Graaff generator is charged up and
join to the water tap as follow.  TP3

Susunan radas Pemerhatian Perbincangan
Arrangement of apparatus Observation Discussion

Pili air Wbearyteabrat Kubah Penunjuk • Kubah penjana Van de Graaff dicaskan
Water tap Insulated Dome galvanometer apabila suis ditutup.
wire The dome of the Van de Graaff generator is
Tali getah terpesong
Rubber belt The pointer of charged up when the switch is closed.
Roda plastik the galvanometer
Plastic wheel • Cas-cas mengalir ke bumi
deflected
apabila kubah penjana Van de Graaff
Galvanometer Penjana Van disambungkan dengan pili air.
Galvanometer de Graaff
Van de Graaff earth
generator The charges flow to the

when the dome of the Van de Graaff

generator is joined to the water tap.

• Galvanometer digunakan untuk mengesan

arus kecil yang mengalir melaluinya.

Galvanometer is used to detect small

current that flows through it.

Hubungan antara Arus Elektrik, Voltan dan Rintangan Buku Teks muka surat 148
The Relationship between Electric current, Voltage and Resistance Textbook page 148

Bab Simbol Arus / Current Voltan / Voltage Rintangan / Resistance
Chapter Symbol I V R
Volt
7 Ampere V Ohm
A
Unit ukuran Voltmeter Ω
Measuring unit Ammeter
Selari
Simbol unit Bersiri Parallel
Unit symbol Series

Alat pengukuran
Measuring tool

Simbol alat ukur
Symbol of measuring tool

Cara menyambung alat
ukur (bersiri / selari)
Ways to connect measuring
tool (series / parallel)

© Nilam Publication Sdn. Bhd. 102

SAINS TINGKATAN 2

Eksperimen 7.1 Hubungan antara Rintangan dan Arus
Experiment Relationship between Resistance and Current

Rancang dan jalankan eksperimen untuk mengkaji hubungan antara rintangan dan arus berdasarkan penyata masalah
di bawah. Anda boleh menggunakan susunan alat radas yang dicadangkan untuk membantu anda dalam rancangan
anda atau anda boleh mereka susunan lain.
Plan and carry out an experiment to study the relationship between resistance and current based on the problem statement
below. You may use the suggested set up of apparatus to help you in your planning or you may design another set up.

Penyata masalah Bagaimanakah perubahan dalam rintangan mempengaruhi arus yang mengalir melalui litar
Problem statement pada voltan tetap?
How does a change in the resistance affect the current flowing through a circuit with a fixed voltage?

Tujuan Untuk mengkaji hubungan antara rintangan dan arus .
Aim
To investigate the relationship between resistance and current .

Hipotesis Semakin tinggi rintangan, semakin kecil arus yang mengalir melalui litar itu.
Hypothesis The higher the resistance, the smaller the current that flows through a circuit.

Pemboleh ubah (a) Pemboleh ubah yang dimalarkan: Voltan, suhu wayar dan dawai nikrom
Variables Constant variable: Voltage, temperature of wire and nichrome wire
(b) Pemboleh ubah yang dimanipulasikan: Panjang dawai nikrom / rintangan
Manipulated variable: Length of nichrome wire / resistance
(c) Pemboleh ubah bergerak balas: Arus / bacaan ammeter
Responding variable: Current / reading of ammeter

Radas dan bahan Ammeter, wayar penyambung, joki, pembaris meter, mentol, wayar nikrom, paku, sel kering Bab
Apparatus and Ammeter, connecting wires, jockey, metre ruler, bulb, nichrome wire, nails, dry cell Chapter
materials
7

Susunan radas Sel kering Ammeter
Arrangement of Dry cells Ammeter
Paku
apparatus Mentol Nail
Bulb
Wayar
Paku Wire
Nail
Wayar nikrom Joki
Nichrome wire Jockey

103 © Nilam Publication Sdn. Bhd.

SAINS TINGKATAN 2 1 Litar disambung seperti dalam rajah.
Prosedur The circuit is connected as in the diagram.
Procedure
2 Satu terminal sel kering disambungkan pada paku di titik A.
One terminal of the dry cell is connected to the nail at point A.

3 Wayar nikrom disentuhkan dengan joki pada titik B yang panjangnya 10 cm dari titik A.
The nichrome is touched with a jockey at point B which 10 cm away from point A.
4 Bacaan ammeter direkodkan.

The reading of the ammeter is recorded.
5 Langkah 3 dan 4 diulangi dengan menambahkan jarak di antara titik A dengan titik B.
Steps 3 and 4 are repeated by increasing the distance between points A and B.
6 Ekperimen diulangi sebanyak dua kali untuk mengurangkan ralat.

The experiment is repeated twice to reduce error.

PEMERHATIAN Jarak A dan B (cm) Bacaan ammeter (A)
OBSERVATION Distance A and B (cm) Reading of ammeter (A)

10 Bacaan 1 Bacaan 2 Bacaan 3
20 Reading 1 Reading 2 Reading 3
30
40 0.50 0.50 0.50
50
0.40 0.45 0.43

0.30 0.30 0.30

0.25 0.20 0.23

0.20 0.20 0.20

Analisis Data 1 Bagaimanakah rintangan dalam litar berubah apabila panjang dawai nikrom meningkat?
Data Analysis How does the resistance in the circuit change when the length of the nichrome wire increases?

Meningkat / Increases

Bab 2 Bagaimanakah arus dalam litar berubah apabila rintangan meningkat?
Chapter How does the current in the circuit change when the resistance increases?

7 Berkurang / Decreases

Kesimpulan 1 Hipotesis diterima .
Conclusion Hypothesis is accepted .

2 Arus berubah secara songsang dengan rintangan. Semakin tinggi rintangan, semakin
kecil arus yang mengalir melalui sesuatu litar.

Current is inversely related to resistance. The higher the resistance, the smaller
the current that flows through a circuit.

© Nilam Publication Sdn. Bhd. 104

SAINS TINGKATAN 2

Eksperimen 7.2 Hubungan antara Voltan dan Arus
Experiment Relationship between Voltage and Current

Penyata masalah Bagaimanakah perubahan dalam voltan mempengaruhi aliran arus elektrik yang melalui
Problem statement sesuatu komponen pada rintangan tetap?
How does a change in the voltage affect the current flowing through a component at a fixed
resistance?

Tujuan Untuk mengkaji hubungan antara voltan dan arus
Aim To investigate the relationship between voltage and current

Hipotesis S emakin tinggi voltan, semakin besar arus yang mengalir melalui sesuatu litar.
Hypothesis
The higher the voltage, the greater the current that flows through a circuit.

Pemboleh ubah (a) Pemboleh ubah yang dimalarkan: Rintangan
Variables Constant variable: Resistance
(b) Pemboleh ubah yang dimanipulasikan: Voltan / Bilangan sel kering
Manipulated variable: Voltage / Number of dry cells
(c) Pemboleh ubah bergerak balas: Arus / Bacaan ammeter
Responding variable: Current / Reading of ammeter

Radas dan bahan Ammeter, voltmeter, mentol, pemegang mentol, pemegang sel kering, suis, wayar
Apparatus and penyambung, sel kering
materials Ammeter, voltmeter, bulb, bulb holder, battery holder, switch, connecting wires, dry cells

Susunan radas Suis Sel kering
Arrangement of Switch Dry cells
Mentol
apparatus Bulb

Bab
Chapter

7

Voltmeter Ammeter
Voltmeter Ammeter

Prosedur 1 Litar disambung seperti dalam rajah.
Procedure The circuit is connected as in the diagram.
2 Suis dihidupkan.
The switch is switched on.
3 Bacaan ammeter dan voltmeter direkodkan.
The readings of the ammeter and voltmeter are recorded.
4 Langkah 2 dan 3 diulangi dengan menggunakan dua, tiga, empat dan lima sel kering.
Steps 2 and 3 are repeated by using two, three, four and five dry cells.

105 © Nilam Publication Sdn. Bhd.

SAINS TINGKATAN 2 Bilangan sel kering Voltan (V) Arus (A) Voltan/Voltage (V)
PEMERHATIAN Number of dry cells Voltage (V) Current (A) Arus/Current (A)
OBSERVATION
1 1.5 0.3 5
2 3.0 0.6
3 4.5 0.9 5
4 6.0 1.2
5 7.5 1.5 5

5

5

Analisis Data Graf voltan melawan arus diplot, kecerunan graf dikira.
Data Analysis Graph voltage against current is plotted, the gradient of the graph is calculated.

Graf voltan melawan arus
Graph voltage against current

Voltan (V) 8 ∆V
Voltage (V) 7 ∆I
6
Bab 5
Chapter 4
3
7 2
1

0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6
Arus (A)
Current (A)

© Nilam Publication Sdn. Bhd. 106

SAINS TINGKATAN 2

1 Apabila bilangan sel kering bertambah, / When the number of dry cells increases,
(i) kecerahan cahaya mentol bertambah .

the brightness of light bulb increases .

(ii) voltan yang merentasi mentol bertambah .
the voltage across the light bulb increases .

(iii) arus yang mengalir melalui litar bertambah . .
the current flowing through the circuit increases

2 (a) Nilai voltan merujuk kepada rintangan litar itu.
arus
voltage
The value of current shows the resistance in the circuit.

(b) Nilai ini kekal apabila voltan dan arus dalam sesuatu litar berubah.

The value is constant when voltage and current of the circuit change.

(c) Dari graf, rintangan adalah bersamaan dengan kecerunan graf.
From the graph, resistance is equivalent to the gradient of the graph.

Kecerunan / Gradient = V2 – V1 = 7.5 – 1.5 =5
I2 – I1 1.5 – 0.3


(d) Hubungan voltan, arus dan rintangan boleh dijelaskan dengan menggunakan

Hukum Ohm iaitu,

Relationship between voltage, current and resistance can be explained using

Ohm’s Law , that is,

Rintangan / Resistance (R) = Voltan / Voltage (V)
Arus / Current (I)
Bab
Chapter

7

Kesimpulan 1 Hipotesis diterima .
Conclusion Hypothesis is accepted .

2 Arus berubah secara terus dengan voltan. Semakin tinggi voltan, semakin

besar nilai arus yang mengalir melalui litar.

Voltage is proportionally related to current. The higher the voltage, the greater

the current that flows through the circuit.

107 © Nilam Publication Sdn. Bhd.

SAINS TINGKATAN 2

Hukum Ohm Buku Teks muka surat 152
Ohm’s Law Textbook page 152

Hukum Ohm / Ohm’s law:

V= IR "Arus elektrik yang mengalir melalui suatu konduktor berkadar terus dengan voltan."
"Electric current that flows through a conductor is directly proportional to the voltage."

Arahan Selesaikan masalah berikut dengan menggunakan Hukum Ohm.
Instruction Solve the following problems by applying Ohm’s Law.  TP4

Contoh / Example Kira rintangan mentol. 1 5V Kira rintangan mentol.
Calculate the resistance of the V Calculate the resistance of the
3V light bulb. 1A A light bulb.

2A A

V

V = R V tutup yang dicari V = R
I IR close what we looking for I
5
3 =R 1 =R
2
R=5Ω
R = 1.5 Ω

2 5V Kira bacaan ammeter jika 3 4V Kira bacaan ammeter jika
rintangan mentol ialah 2 Ω. V rintangan mentol ialah 2 Ω.
A Calculate the reading of A Calculate the reading of
ammeter if the resistance of ammeter if the resistance of
the bulb is 2 Ω. the bulb is 2 Ω.

V V V
I I
= R = R

5 =2 4 =2
I I
Bab
Chapter I = 2.5 A I=2A

7

4 Kira bacaan voltmeter jika 5 Kira bacaan voltmeter jika
rintangan mentol ialah 2 Ω. rintangan mentol ialah 3 Ω.
2A A Calculate the reading of 1A A Calculate the reading of
voltmeter if the resistance of voltmeter if the resistance of
the bulb is 2 Ω. the bulb is 3 Ω.

V V

V = R V = R
I I

V = 2 V = 3
2 1

V=4V V=3V

Refleksi Murid Sila tandakan (3) Faham / Understand (    ) Kurang faham / Less understand (    ) Tidak faham / Do not understand (    )
Please tick (3)
Studentsʼ 108
Reflection

© Nilam Publication Sdn. Bhd.

SAINS TINGKATAN 2

7.2  Pengaliran Arus Elektrik dalam Litar Bersiri dan Litar Selari

Electrical Current Flows in Series Circuit and Parallel Circuit

SP 7.2.1 K.Kejayaan / S.Criteria
LS
Menghuraikan dan berkomunikasi mengenai pengaliran arus elektrik dalam litar bersiri dan litar selari. / Elaborate and
EMK communicate about the flow of electric current in series circuit and parallel circuit.

Nilai Murni Kemahiran saintifik (proses pemikiran dan kemahiran manipulatif tertentu) / Scientific skills (specific processes of thinking and manipulative skills)
Moral Value
Jujur dan tepat dalam merekod dan mengesahkan data
Honest and accurate in recording and verifying data

Komponen Litar Elektrik Buku Teks muka surat 152
Electrical Circuit Components Textbook page 152

1 Suatu litar yang lengkap membenarkan arus mengalir melaluinya dan alat elektrik yang disambung
dalamnya boleh berfungsi . to flow through it and the electrical appliances in it can

A complete circuit allows a current

function .  TP1

2 Lukiskan simbol-simbol bagi semua komponen di bawah. / Draw the symbol of all components.  TP1

Komponen Simbol Komponen Simbol
Component Symbol Component Symbol

Sel kering Perintang
Dry cell Resistor

Suis Fius
Switch Fuse

Voltmeter V Galvanometer G
Voltmeter Galvanometer

Ammeter A
Ammeter
Mentol lampu Perintang boleh ubah or / atau
Rheostat (variable resistor)
Bulb
+– Bab
Chapter

7

Litar Bersiri dan Litar Selari Buku Teks muka surat 153
Series Circuit and Parallel Circuit Textbook page 153

+– +–

Litar bersiri / Series circuit 109 Litar selari / Parallel circuit
© Nilam Publication Sdn. Bhd.
+–

SAINS TINGKATAN 2

1 Lengkapkan kelebihan dan kelemahan litar bersiri dalam jadual di bawah.
Complete the advantages and disadvantages of series circuit in the table below.  TP4

Kelebihan litar bersiri Kelemahan litar bersiri
Advantages of series circuit Disadvantages of series circuit

• Menggunakan hanya satu suis untuk • Apabila satu mentol terbakar, mentol lain
menghidupkan semua mentol. terpadam . / When one bulb burns out, all the other

Use only one switch to switch on all bulbs. bulbs go off .

• Voltan akan meningkat apabila • Kecerahan mentol berkurang apabila lebih banyak
mentol disambungkan . / The brightness of the bulbs
sel-sel kering disambungkan secara
bersiri.
. decreases when more bulbs are connected .

Voltage increases when dry cells are • Mentol tidak boleh dipadam berasingan.

connected in series . Light bulb cannot switched off separately.

2 Lengkapkan kelebihan dan kelemahan litar selari dalam jadual di bawah.
Complete the advantages and disadvantages of parallel circuit in the table below.  TP4

Kelebihan litar selari Kelemahan litar selari
Advantages of parallel circuit Disadvantages of parallel circuit

• Kecerahan mentol bertambah apabila lebih banyak • Voltan setiap alat elektrik tidak dapat
mentol disambungkan . / The brightness of the bulb dikawal
kerana voltannya
sama dengan voltan sumber.
increases when more bulbs are connected . Voltage for each of electrical appliance cannot

• Mentol boleh dihidupkan dan dipadamkan secara be controlled because its voltage
berasingan .
same as source voltage.
Bulbs can be switched on or off separately .
• Tenaga sel kering dihabiskan dengan lebih
• Jika terdapat satu mentol atau alat elektrik rosak, alat lain cepat
masih berfungsi . / If one bulb or electrial appliance .
Energy of the dry cells is used up

burns out, the other appliances still function . faster .

Bab 3 Bandingkan arus, voltan dan rintangan dalam litar bersiri dan litar selari dalam jadual di bawah.
Chapter Compare the current, voltage and resistance in a series circuit and a parallel circuit in the table below.  TP2

7

Ciri-ciri / Properties Litar bersiri / Series circuit Litar selari / Parallel circuit

Susunan komponen V V
Arrangement of
components I I I1 V1R1
I2 V2R2
V1R1 V2R2

I1 I2

Arus / Current I = I1 = I2 I = I1 + I2
Voltan / Voltage V = V1 + V2
Rintangan berkesan V = V1 = V2
Effective resistance R = R1 + R2
1 = 1 + 1
R R1 R2

© Nilam Publication Sdn. Bhd. 110

SAINS TINGKATAN 2

Penyelesaian masalah pengiraan / Problem solving on calculation
1 Selesaikan masalah berikut tentang voltan, arus dan rintangan dalam litar bersiri atau selari.
Solve the following problems on voltage, current and resistance in a series or parallel circuit.  TP2

(a) Diberi voltan dalam litar ialah 9 V dan jumlah arus ialah 2 A.
Given the voltage in the circuit is 9 V and the total current is 2 A.

2Ω r

(i) Kirakan jumlah rintangan dalam litar (ii) Kemudian, cari rintangan r.
tersebut. Then, find out the resistance of r.
Calculate the total resistance in the circuit. R = R1 + R2
4.5 = 2 + r
R = V r = 2.5 Ω
I
9
= 2

= 4.5 Ω

(b) Diberi bacaan voltmeter ialah 6 V dan jumlah arus dalam litar ialah
3 A. Dua mentol tersebut adalah sama.
Given the reading of the voltmeter is 6 V and the total current in the
circuit is 3 A. The two bulbs are identical.

V (ii) Kirakan rintangan setiap mentol.
Calculate the resistance of one light bulb.
(i) Apakah voltan yang dibekalkan kepada 1 1+1
setiap mentol? R= V R = R1 R2
What is the voltage supplied to each I 1 = 1+1
6 2 = R21 R2
light bulb? = 3 1 R1 (R2 = R1)
6V 2

=2Ω Bab
Chapter
R1 = 4 Ω
7

Projek / Project PdPc
1 Sediakan satu lakaran ringkas litar yang sesuai digunakan di rumah. 21

Prepare a sketch on simple suitable circuit used at home.
2 Wajarkan pemilihan jenis litar yang anda gunakan dalam lakaran di (1).
Justify the sketch you draw in (1).

Refleksi Murid Sila tandakan (3) Faham / Understand (    ) Kurang faham / Less understand (    ) Tidak faham / Do not understand (    )
Please tick (3)
Studentsʼ 111 © Nilam Publication Sdn. Bhd.
Reflection

SAINS TINGKATAN 2

7.3  Kemagnetan / Magnetism

7.3.1 K.Kejayaan / S.Criteria
SP 7.3.2
LS Merumuskan ciri magnet. / Draw a conclusion about the characteristics of a magnet.

7.3.3 Menghuraikan dan berkomunikasi mengenai elektromagnet. / Describe and communicate about electromagnets.

EMK Menjalankan eksperimen dan berkomunikasi mengenai kegunaan magnet dan elektromagnet dalam kehidupan
Nilai Murni seharian. / Carry out an experiment and communicate the uses of magnets and electromagnets in daily life.
Moral Value
Kemahiran saintifik (proses pemikiran dan kemahiran manipulatif tertentu) / Scientific skills (specific processes of thinking and manipulative skills)

Jujur dan tepat dalam merekod dan mengesahkan data
Honest and accurate in recording and verifying data

Sifat-sifat Magnet Buku Teks muka surat 158
Properties of Magnet Textbook page 158

1 Magnet ialah oksida sesetengah logam. Daya magnetik magnet menarik bahan-bahan magnet.
A magnet is an oxide of certain metals. The magnetic force of a magnet attracts magnetic substances.  TP1

2 Antara berikut, yang manakah merupakan bahan-bahan magnet? Tandakan (✓) dalam kotak.
Which of the following are magnetic substances? Tick (✓) in the box.  TP1

Besi / Iron ✓ Karbon / Carbon Keluli / Steel ✓
Nikel / Nickel
✓ Kobalt / Cobalt ✓ Aluminium / Aluminium

3 Magnet ada dua kutub, iaitu kutub utara dan kutub selatan .
pole and
A magnet has two poles, north south pole.  TP2

Kutub yang sama menolak antara satu Kutub yang berbeza menarik antara

Bab sama lain. satu sama lain.
Chapter Different poles
Same poles repel each other. attract each other.
7

4 Apabila sebatang magnet bar digantung bebas, kutub utaranya menghala ke Utara Bumi.

When a bar magnet is hung free, its north pole points to North of Earth.  TP2

Disebabkan sifat magnet ini, kompas
dicipta untuk menentukan arah. compass
Due to this characteristic of magnet,
U/N
is invented to determine direction.

5 Medan magnet: Kawasan sekitar magnet yang wujud kesan daya oleh magnet.
Magnetic field: The area force by the magnet.  TP1
around the magnet that has the effect of
© Nilam Publication Sdn. Bhd.
112

SAINS TINGKATAN 2

Medan Magnet Buku Teks muka surat 159
Magnetic Field Textbook page 159

1 Rajah di bawah menunjukkan sebatang magnet bar. Bagi mengkaji corak medan magnet:
Diagram below shows a bar magnet. To study the pattern of a magnetic field:

(a) Lukis arah jarum kompas-kompas tersebut. (b) Lukis garisan medan magnet yang terbentuk.
Draw the direction of the pointers of the compasses. Draw the magnetic field lines formed.

U/N S/S U/N S/S

2 Arah garisan medan magnet bermula dari kutub utara dan tamat pada kutub selatan

magnet bar. Garisan medan magnet adalah lebih dekat di kutub dan berpisah lebih jauh antara satu sama lain di
sisi magnet bar. Ini adalah kerana medan magnet di sekitar kutub adalah lebih kuat .

The direction of the magnetic field lines begins from the north pole and ends at the south

pole of the bar magnet. The magnetic field lines are closer at the poles and further apart from one another at the
side of the bar magnet. This is because the magnetic field around the poles is stronger .

Latihan / Exercise
Lukiskan medan magnet. / Draw the magnetic fields.  TP3

U/N S/S U/N S/S Bab
S/S U/N U/N S/S Chapter

7

U/N S/S U/N
S/S
113
© Nilam Publication Sdn. Bhd.

SAINS TINGKATAN 2

Keelektromagnetan Buku Teks muka surat 160
Electromagnetism Textbook page 160

1 Elektromagnet merupakan medan magnet yang dihasilkan oleh konduktor yang dikenakan Ekstra / Extra

arus dan hanya bersifat sementara .

An electromagnet is a field of magnetic that produced by the conductor with flowing current

and it is temporary .

2 Apabila arus terhenti, medan magnet juga hilang.
When the current is stopped, magnetic field also stopped.

3 Arah medan magnet disongsangkan apabila arus elektrik disongsangkan.

The direction of the magnetic field is reversed when the direction of the current is reversed.

4 Arah medan magnet boleh ditentukan dengan menggunakan petua genggaman tangan kanan seperti dalam
rajah di bawah. right-hand grip rule as in the following

The direction of the magnetic field can be determined by using the
diagram.

I (arus) I (arus) • Ibu jari tangan kanan menunjukkan arah arus .
I (current) I (current)

The thumb of the right hand shows the direction of current .

• Jari-jari lain menunjukkan arah medan magnet

apabila dipandang dari atas.
Other fingers show the direction of the magnetic field
Medan magnet Tangan kanan when seeing from above.
Magnetic field Right hand

5 Melukis corak medan magnet yang disebabkan oleh: / Draw the pattern of the magnetic field due to:  TP3

(a) Arus dalam wayar lurus Penyelesaian
Current in a straight wire Solution

Bab
Chapter

7

(b) Arus dalam gegelung tunggal Penyelesaian
Current in a single coil Solution

© Nilam Publication Sdn. Bhd. 114

SAINS TINGKATAN 2

Eksperimen 7.3 Untuk Menentukan Kekuatan Elektromagnet Eksperimen Wajib
Experiment To Determine the Strength of an Electromagnet
Compulsory Experiment

Tujuan Mengkaji hubungan antara kekuatan Mengkaji hubungan antara kekuatan
Aim elektromagnet dengan arus elektromagnet dengan bilangan lilitan

To investigate the relationship between gegelung
the strength of an electromagnet and the To investigate the relationship between the
strength of an electromagnet and the number
current
of turns of the coil
Untuk mengkaji hubungan antara kekuatan
elektromagnet dan arus. Untuk mengkaji hubungan antara kekuatan
To investigate the relationship between the elektromagnet dan bilangan lilitan gegelung.
strength of an electromagnet and the current. To investigate the relationship between the
strength of an electromagnet and the number of
Hipotesis Kekuatan elektromagnet (berdasarkan bilangan turns of coil.
Hypothesis paku yang terlekat kepada elektromagnet)
bertambah apabila arus elektrik bertambah. Kekuatan elektormagnet (berdasarkan bilangan
The strength of an electromagnet (indicated by paku yang terlekat kepada elektromagnet)
the number of nails attached to the bertambah apabila bilangan lilitan gegelung
electromagnet) increases as the current bertambah. / The strength of an electromagnet
increases. (indicated by the number of the nails attached to
the electromagnet) increases as the number of
Pemboleh Pemboleh ubah dimanipulasikan: Arus turns of coil increases.
ubah Manipulated variable: Current
Variables Pemboleh ubah bergerak balas: Bilangan paku Pemboleh ubah dimanipulasikan: Bilangan
yang terlekat kepada elektromagnet lilitan gegelung

Responding variable: The number of nails Manipulated variable: The number of turns of

attached to the electromagnet coil
Pemboleh ubah dimalarkan: Bilangan lilitan
gegelung, jenis teras Pemboleh ubah bergerak balas: Bilangan paku
yang terlekat kepada elektromagnet
Constant variable: The number of turns of Bab
coil, type of the core Responding variable: The number of nails Chapter

Senarai Ammeter, wayar penyambung, reostat, kaki attached to the electromagnet 7
bahan dan retort, suis, bekalan kuasa a.t., teras besi Pemboleh ubah dimalarkan: Arus, jenis teras
radas lembut, dawai kuprum, paku besi kecil dan
List of bekas plastik. Constant variable: Current, type of core
materials Ammeter, connection wires, rheostat, retort
and stand, switch, d.c. supply, soft iron core, copper Ammeter, wayar penyambung, reostat, kaki
apparatus wire, small iron nails and plastic container. retort, suis, bekalan kuasa a.t., teras besi lembut,
dawai kuprum, paku besi kecil dan bekas plastik.
Ammeter, connection wires, rheostat, retort stand,
switch, d.c. supply, soft iron core, copper wire, small
iron nails and plastic container.

Susunan Teras besi Dawai kuprum / Copper wire Teras besi Dawai kuprum / Copper wire
radas lembut lembut
Arrangement Soft iron Bekas Soft iron Bekas
of the core plastik core plastik
apparatus Plastic Plastic
Paku besi container Paku besi container
kecil kecil
Small iron Small iron
nails nails

115 © Nilam Publication Sdn. Bhd.

SAINS TINGKATAN 2

1 Suis dihidupkan. 1 Suis dihidupkan.
The switch is switched on. The switch is switched on.
2 Bacaan ammeter direkodkan, I = 0.1 A 2 Bilangan lilitan gegelung direkodkan, M = 5
The reading of the ammeter is recorded, The number of turns of coil is recorded,

I = 0.1 A M = 5
3 Hujung bawah gegelung ditetapkan 3 Hujung bawah gegelung ditetapkan pada
pada jarak, H, dari bekas plastik yang jarak, H, dari bekas yang mengandungi paku
mengandungi paku besi kecil. besi.
The lower end of the coil is fixed at a height, The lower end of the coil is fixed at a height, H,

H, from the plastic container full of small iron from the container full of small iron nails.
4 Bekas plastik dialihkan dan bilangan paku
Prosedur nails. yang tertarik kepada elektromagnet, N dikira
Procedure 4 Bekas plastik dialihkan dan bilangan paku dan dicatat.

yang terlekat kepada elektromagnet, N
dikira dan dicatatkan. The plastic container is removed and the

The plastic container is removed and number of nails attached to the electromagnet,

the number of nails attached to the N is counted and recorded.
electromagnet, N are counted and recorded. 5 Eksperimen diulang dengan bilangan lilitan
5 Eksperimen diulang dengan nilai arus, yang gegelung yang berbeza, M = 10, 15, 20, 25
berbeza, I = 0.2 A, 0.3 A, 0.4 A dan 0.5 A The experiment is repeated with different
dengan melaraskan reostat. number of turns of coil, M = 10, 15, 20, 25

The experiment is repeated with different

values of current, I = 0.2 A, 0.3 A, 0.4 A and

0.5 A by adjusting the rheostat.

Arus, I 0.1 0.2 0.3 0.4 0.5 Bilangan lilitan, 5 10 15 20 25
Current, A Number of turns, M 23456
Bilangan paku besi
Bilangan paku besi yang terlekat kepada
Pemerhatian yang terlekat kepada
Observation elektromagnet elektromagnet
Number of iron nails 2 3 4 5 6 Number of iron nails

attached to the attached to the
electromagnet, N electromagnet, N

Hipotesis diterima . Kekuatan Hipotesis diterima . Kekuatan

elektromagnet meningkat apabila arus elektromagnet meningkat apabila bilangan lilitan
Bab Kesimpulan meningkat. gegelung meningkat.
Chapter Conclusion
Hypothesis is accepted . Strength of Hypothesis is accepted . Strength of
7
electromagnet increases when current increases. electromagnet increases when number of turns of

coil increases.

Projek / Project

  Arahan / Instructions: PdPc
21

Secara berkumpulan, cari maklumat mengenai aplikasi elektromagnet dari sebarang sumber dan persembahkan
dalam bentuk slaid kepada rakan sekelas.
In group, find information about application of electromagnet from any source and present it in slide show to the

classmates.  TP6

Refleksi Murid Sila tandakan (3) Faham / Understand (    ) Kurang faham / Less understand (    ) Tidak faham / Do not understand (    )
Please tick (3)
Studentsʼ 116
Reflection

© Nilam Publication Sdn. Bhd.

SAINS TINGKATAN 2

LATIHAN PENGUKUHAN / ENRICHMENT EXERCISE

1 Rajah 1 menunjukkan dua jenis litar, J dan K.
Diagram 1 shows two types of circuits, J and K.

JK
Rajah 1 / Diagram 1

(a) Jika salah satu mentol dalam litar telah rosak, litar yang manakah akan berfungsi? Sila tandakan (3) pada
kotak yang betul.

If one of the bulbs in the circuit is malfunctioned, which of the circuit will still be functioning? Please tick (3) in the
box correctly.

J K3

[1 markah/mark]

(b) Jika dua sel kering 1.5 V digunakan dalam litar J, apakah rintangan bagi setiap mentol jika arus yang direkodkan
oleh ammeter ialah 0.5 A?
If two 1.5 V dry cells are used in circuit J, what is the resistance for each bulb if the current recorded by the ammeter

is 0.5 A?
V = IR
2 × 1.5 V
R= V = 0.5 A = 6 Ω
I
Rintangan 2 mentol / Resistance 2 bulbs = 6 Ω

Rintangan 1 mentol / Resistance 1 bulb = 6 Ω = 3 Ω
2
[3 markah/marks]

(c) Berikan dua kelebihan jenis litar K. Bab
Give two advantages of circuit K. Chapter
– Jika satu mentol terbakar, satu mentol lagi masih menyala.
7
If one bulb burns out, another bulb still lights up.
– Setiap mentol menerima voltan penuh daripada sumber dan kecerahan sama. [2 markah/marks]

Each bulb receives full voltage from the source and have the same brightness.

117 © Nilam Publication Sdn. Bhd.

SAINS TINGKATAN 2

2 Rajah 2 menunjukkan sebatang paku besi dililitkan dengan wayar yang disambungkan kepada sebiji bateri.
Diagram 2 shows an iron nail coiled with wire and connected to a battery.

NS

–+

Rajah 2 / Diagram 2 [1 markah/mark]
(a) Apakah yang terhasil dalam eksperimen ini?
What is produced in this experiment?

Elektromagnet / Electromagnet

(b) Cadangkan dua cara yang boleh menambahkan kekuatan produk di (a). [2 markah/marks]
Suggest two methods that can increase the strength of the product in (a).
– Menambah lilitan wayar.

Increase the number of coils of the wire.
– Menambah bilangan bateri.

Increase the number of batteries.

(c) Berikan satu contoh mesin yang menggunakan prinsip eksperimen ini. [1 markah/mark]
Give one example of machine that uses the principle of this experiment.
Kren / Crane

(d) Nyatakan satu kelebihan dan satu kelemahan produk yang terbentuk dalam eksperimen ini berbanding
magnet kekal.

State one advantage and one disadvantage of the product formed in this experiment compared to a permanent
magnet.

Bab Kelebihan / Advantage:

Chapter

7 Kesan magnet dapat diubah mengikut keperluan.

The magnetic effect can be changed according to requirement.

Kelemahan / Disadvantage:
Memerlukan tenaga elektrik untuk berfungsi.

Requires electrical energy to operate.

[2 markah/marks]

Ekstra / Extra

© Nilam Publication Sdn. Bhd. 118