Grade 7 UNIT P.3 Magnetism

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MAGNETISM

Grade 7 UNIT P.3 Magnetism

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Curriculum standards:

7.19.1, 7.19.2, 7.19.3, 7.19.4, 7.19.5, 7.19.6

Objectives:

1-Distinguish between magnetic and non magnetic materials

فشق ث اناد انغبغضخ انغش يغبغضخ2- Define magnetic materials ؼشف اناد اناد انغبغضخ

3- Define non-magnetic material ؼشف اناد انغش يغبغضخ

4- How to make a permanent magnet from mild steel.

ؤلذ ي يبدح انضزم؟كف صغ يغبغش و

KEY WORDS

Magnet يغبغش

Attraction اجزاة

Magnetic

materials

ياد رجزة

نهغبغش

Non-

magnetic

materials

ياد ال رجزة

نهغبغش

North pole انمطت انشبن

South pole انمطت انجث

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What is a magnet? طيس؟ ما هو المغنا

A Magnet is mostly made of iron, steel, or nickel. It attracts some

metals.

صغ انغبغش ثشكم اصبص ي انحذذ انضزم انكم جزة اناد انصػخ ي ثؼط انؼبد

Magnetic and non-magnetic materials:

:اناد انغبغضخ انغش يغبغضخ It really doesn’t matter how long this student tries to

pick up these pieces of paper with her magnet, she is

not going to succeed.

ال ى انفزشح انز رحبل فب ز انفزبح انزمبغ االساق ثبصزخذاو انغبغش الب ن

رفهح ف رنكMagnets will only attract objects that are made from

magnetic materials, such as iron, steel nickel and

cobalt, and we call them magnetic materials.

يثم انحذذ انكم انكثهذاناد انغبغضخ ضزطغ انغبغش ا جزة فمػ

Paper is a non-magnetic material: a magnet does not attract it

Other examples of non- magnetic materials include wood, plastic

aluminum and copper.

.ال ضزطغ انغبغش ا جزثب، يثم انسق، انخشت، االنو، انحبس اناد انغش يغبغضخ

Grade 7 UNIT P.3 Magnetism

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How to make a magnet? كف صغ انغبغش؟

Iron and steel are the most common magnetic materials, and are

easily magnetized. انحذذ انكم ي اناد انز ضم رحهب نغبغش

1. Stroking method: غشمخ انحك

If you take a needle and stroke a strong magnet

along it several times in the same direction, the

needle will become magnetized, the stroking

(organizes) the magnetic particle inside the

needle.

ػذ حك اثشح ثغبغش ف ارجب احذ نؼذح يشاد فبب رصجح يغبغش

ثضجت اػبدح رشرت انجزئبد انغبغضخ ثذاخهب

2. Electrical Method (electromagnet) : انطشمخ انكشثخ

Wind an insulated copper wire around a large nail.

Then connect the ends of the wires to a battery,

the nail will become a magnet.

ػذ نف صهك حبص يؼزل حل يضبس رصم انضهك ثجطبسخ فب

انضبس زحل ان يغبغش

Inside a magnet:

A magnet is often made of iron, we can think of a

bar of iron as being made up of lots of tiny

magnets called domains. The small magnetic

effect of each tiny magnet is lost because they

are all pointing in different directions.

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Where is the magnet strongest site? What we call

these sites? ا ك انغبغش ل يبرا ض زح األيبك؟

Activity: : شبغ

Spread some iron filings onto a piece of paper which is over a bar

magnet to see where are the parts mostly attracted

ب انجشادحاثش ثشادح انحذذ ػه يغبغش اطش يب االجزاء انز رجزة ان

Draw your results on a piece of paper ارسم اننتيجة

If we sprinkle some iron filings onto magnet they will attract to the

ends. It is here where the magnet is strongest. These are called

poles of a magnet

Most magnets have two poles, a north pole and a south pole

ػذ ثش ثشادح انحذذ ػه انغبغش فبب رجزة

ألغشاف انغبغش، انبغك انز ك فب

رض االلطبةانغبغش اكثش لح

نكم يغبغش لطت شبن اخش جث

If a bar magnet is suspended in a paper

stirrup, providing there are no other

magnets or magnetic material Close by it

will rest in a North-South direction

يبن ن ارا رى رؼهك يغبغش ثمطؼخ ي انسق فب انمطت انش

زجخ ان انمطت انشبن انجغشاف نالسض

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Worksheet

Q1: Define the following: عرف ما يلي

a- Magnetic material المواد المغناطيسية

________________________________________________

________________________________________________

b- Non-magnetic materials المواد الغير مغناطيسية

……………………………………………………………………………………………………………………

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

Q2: Sort the materials inside the box to magnetic and non magnetic

material صنف ما يلي الى مواد مغناطيسية وغير مغناطيسية

Cotton – cobalt – steel fork – plastic - iron –

Aluminum key – wood - glass - copper - nickel

Magnetic material: اناد انغبغضخ

……………………………………………………………………………………………………………………………

Non Magnetic material: اناد انغش يغبغضخ

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

Q3: Complete: اكم يب ه

1) The strongest part of magnet is called………………………………

....................................االجزاء انمخ ي انغبغش رض

2) The magnet has …………. Poles, they are called ………………….and

…………………………

.....................لطت........................لطت: ، ضب............................انغبغش ن

3) If you stroke a needle with a strong magnet along it several

times in the same direction, it will become a………………………………….

.........................رصجحػذ حك اثشح ثغبغش ل ػذح يشاد ف فش االرجبح فبب

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Objectives

1- Know that similar magnetic poles repel each other and opposite

poles attract each other.

انغبغضخ انزشبثخ رزبفش االلطبة انخزهفخ رزجبرة ؼشف ا االلطبة 2- Distinguish between an object that is a magnet and one that is

attracted to a magnet.

فشق ث انجضى انز ثزار يغبغش ث اناد انز رجزة نهغبغش3- Understand that the test for magnetism is repulsion

فى ا اخزجبس انغبغش انزبفش4- Know that magnetic fields act through non-magnetic

material. ؼهى ا انجبل انغبغض إثش ػجش اناد انغش يغبغضخ

KEY WORDS

Attract جذب

Attraction جاذبية

Repel طرد

Repulsion

Like poles

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Magnetic force (attraction and repulsion):

(انزجبرة انزبفش)انم انغبغضخ

If two similar poles are placed near each other they will repel each

other. ػذ ظغ لطجب يغبغضب يزشبثب ثجبت ثؼعب فبب زبفشا

If two dissimilar poles are placed near each other they attract ارا رى ظغ الطبة يغبغضخ يخزهفخ ثجبت ثؼعب فبب زجبرثب

Like poles repel each other, unlike poles attract each other

االلطبة انزشبثخ رزبفش االلطبة انخزهفخ رزجبرة

Test of magnetism: س انغبغضخ اخزجب

Which is a magnet and which is a magnetic material?

Because magnets can be repelled as will as attracted

To other magnets, we can sort magnet from magnetic material.

The picture shows three objects, two are

magnets and one is a piece of steel. Each

magnet has two poles. Both poles of both

magnets attract the steel object but one end

of one magnet will repel one end of the other

magnet. رظح انصسح ثالس اجضبو، اثب يب يغبغش االخش لطؼخ ي انضزم،

غضب جزثب لطؼخ انضزم نك احذ غشف انغبغش زبفش يغ نكم يغبغش لطجب، لطجب كال انغب

احػ غشف انغبغش االخش

To be sure a material is a magnet is to test for

repulsion. نك زأكذ اب يغبغش فب االخزجبس انزبفش If the magnet repels an object, then the object is also a magnet

ارا ربفش انغبغش يغ جضى فب زا انجضى يغبغش اعب

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Activity:

Use the following information about the three

blocks in the picture to know which one of

them is the block of steel اصزخذو انؼهيبد انزبنخ نهزؼشف ػ انغبغش ي ث االجضبو انثالثخ

يظحخ ف انصسحال Both ends of A always attract B

B انجضى رجزة دائب A انجضىغشفب

Both ends of C always attract B

Bرجزة دائب انجضى C غشفب انجضى

Each end of A attracts one end of C and repels the other end.

ف االخش نرزبفش يغ انطش Cاحذ اغشاف انجضى رجزة A غشفب انجضى

Object …………… is the block of steel لطؼخ انضزم........انجضى

As ……. and ……are the magnets because they……………….each other.

ثؼعب انجؼط.....................يغبغضبد الب............ ......... انجضى

Magnetic fields act through non-magnetic materials.

انجبل انغبغض إثش ػجش اناد انغش يغبغضخSome of non-magnetic materials such as paper and water can let the

force of magnetism pass through them while magnetic materials,

such as a steel sheet, do not let the force of magnetism pass

through them.

ثؼط اناد انغش يغبغضخ يثم انسق انبء رضح نهم انغبغضخ ثبنشس ي خالنب ثب اناد

انغبغضخ يثم انضزم ال رضح نهم انغبغضخ ثبنشس ي خالنب

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Worksheet

Q1: Choose the correct answer: اخزبس االجبثخ انصححخ

1) To be sure a material is a magnet we test for

:نهزبكذ ثب انبدح يغبغش فب االخزجبس

a) attraction b) repulsion c) both

2) Magnetism can pass through لح انغبغش رش ي خالل

a) water b) paper c) both

Q2: True or false: صح ا خطأ

a) When we sprinkle some iron filings onto a bar magnet, they will

be attracted in the middle of the bar ( )

) (اب رجزة نزصف انغبغش ػذ ثش ثشادح انحذذ ػه يغبغش ف

b) Unlike poles repel each other ( )

) (االلطبة انغش يزشبثخ رزبفش

Q3: Show on the diagram below where the iron filings collect, if you

sprinkle them over a bar magnet:

N S

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Objectives: -

1- Demonstrate the pattern of the lines of force of a magnetic

field around a magnet using iron filings and a compass. ثم خطغ انجبل انغبغض ثبصزخذاو ثشادح انحذذ ثصهخ

Magnetic field: Area around the magnet in which the pull of the

Magnetic force can act.

غش انز ظش فب اثش انمح انغبغضخانجبل انغبغض انطمخ انحطخ ثبنغب Magnetic field lines: -lines that show the shape of a magnetic field.

انخطغ انز رثم شكم انجبل انغبغض: خطغ انجبل انغبغض

When an object made of iron or steel is placed close to the magnet

it is attracted towards the magnet even it is not in contact, this

happened because the object is inside the magnetic field of a

magnet. ػذ ظغ جضى يصع ي انحذذ ا انضزم ثبنمشة ي يغبغش فب جزة ان حز ا نى ك

داخم انجبل انغبغض نهغبغش اليض، زا حذس ال انجضى

Discover the shape of the magnetic

field: اكتشاف شكم انمجال انمغناطيسي

1-By using iron filings ثبصزخذاو ثشادح انحذذ

Place a piece of paper over the magnet and

then sprinkle iron filings gently over the

paper. The pattern formed by the filings

show the shape of a magnetic field.

ظغ لطؼخ ي انسق فق يغبغش اثش ػهب ثشادح انحذذ، رشرت ثشادح انحذذ ظح شكم انجبل

.انغبغض

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2-By using a small compass ثبصزخذاو ثصهخ صغشح

Place a magnet on a piece of paper, and then

place small plotting compasses next to the

magnet, a circle drawn and the direction in which

the compass point marked inside a circle. ظغ يغبغش ػه لطؼخ ي انسق، ظغ فلب ػذح ثصالد صغشح،

نغبغضانذائشح انز رشصب انجصالد ارجبب ثم انجبل ا

LOOK AT THE PICTURE BELOW CAREFULLY IT SHOWS BOTH

THE TWO WAYS OF FINDING THE SHAPE OF THE MAGENTIC

FIELD:

The properties of magnetic field lines خاص انجبل انغبغض

1- Always travel from north to south pole زج دائب ي انمطت انشبن نهجث

2- Show the strength of a magnet, if the lines close together the

field is strong, but if the lines are separated the field is

weak. ظح لح انغبغش، ارا كبذ خطغ انجبل لشجخ ي ثؼعب انجؼط ك انجبل انغبغض ل

ثب ارا كبذ انخطغ ثؼذح ػ ثؼعب ك انجبل انغبغض ظؼف

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Q1: Define: ػشف

Magnetic field:انجبل انغبغض

……………………………………………………………………………………………………………………………

Magnetic field lines:خطغ انجبل انغبغض

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

Q2: True or false: صح او خطأ

1) Magnetic field lines always travel from south to north ( )

نهشبن انجبل انغبغض زج دائب ي انمطت انجث

2) The close the Magnetic field lines the stronger the field ( )

ارا كبذ خطغ انجبل لشجخ فب انجبل ك ال

Q3: Draw the Magnetic field lines: اسصى خطغ انجبل انغبغض

Q4: Use the picture to know which one is the north pole

in the magnet.

اصزخذو انشصى نؼشفخ اب انمطت انشبن اب انجث نهغبغش

S N

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The earth’s magnetic field انجبل انغبغض نالسض

Objectives: -

1- Recognise that the earth has a magnetic field and realize that

the earth south magnetic pole is in its geographical north and

vice versa. ؼشف ا نألسض يجبل يغبغض ا انجبل انجث انغبغض نألسض لطجب انشبن

انجغشاف

*The earth is surrounded by a magnetic field .Its shape and

direction is as if there is a giant magnet buried within the earth

*The earth south magnetic pole is in its geographical north

*The earth north magnetic pole is in its geographical south.

* The magnetic field lines are not flat, they are three dimensional

انغبغض نالسض كأ االسض ثب يغبغش ػالق االسض يحبغخ ثجبل يغبغض، شكم انجبل

انمطت انشبن انغبغض نالسض لطجب انجغشاف انجث

انمطت انجث انغبغض نالسض لطجب انشبن انجغشاف

خطغ انجبل انغبغض نالسض ثالث االثؼبد نش يضطحب

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Worksheet

Q1: Show the poles of the magnet inside the earth, and then draw

the lines of earth’s magnetic field

غغ انجبل انغبغضظح الطبة انغبغش ف داخم االسض، ثى اسصى خ

Q2: Complete: اكم

1) The earth’s south magnetic pole is in its geographical……………………

انجغشاف.........................انمطت انجث انغبغض نألسض مغ ف لطجب

2) The earth’s north magnetic pole is in it’s ……………… ……………………

.....................................................لطت االسض انشبن انغبغض مغ ف