7.3 magnetism (offline workbook discussion)

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
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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
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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

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