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Grade 3 Unit P.2 Light, Shadows and Mirrors 1 Light, S S h h a a d d o o w w s s and Mirrors

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Grade 3 Unit P.2 – Light, Shadows and Mirrors

1

Light,

SShhaaddoowwss and Mirrors

Grade 3 Unit P.2 – Light, Shadows and Mirrors

2

Standards of the unit معايير هذه الوحدة

1.2 Make a test prediction and draw conclusions

from observation and data.

1. Make systematic observation and observe

patterns.

2.3 use labeled pictures to communicate

observations.

2.4Use words in their scientific contest

3.1 Handle simple equipment correctly, safely and

without damage to carry out simple objects.

11.1 Explain that shadows occur when a light source

is blocked by an object.

11.2 Recognize that the shape of a shadow is

similar to the shape of the object that makes it.

11.3 Show that light can pass through a

transparent object but not through an opaque one.

11.4 Know that many objects are transparent only

to light of a particular color.

11.5 Know that light can be reflected by mirrors.

11.6 Use a magnifying glass to focus light.

11.7 Know that heat and light have many similar

properties.

Grade 3 Unit P.2 – Light, Shadows and Mirrors

3

Sources of light مصادر الضوء

1) light sources give out light مصدر الضوء هو الذي

عطنا الضوء مباشرة مثل

Examples:

1- The sun الشمس

2- Stars النجوم

3- Candle flame الشمعة

4- Electric light

الكهربائ المصباح

Remember! You must never look directly at the

sun. It is so bright that it can damage your eyes

very quickly. ممكن أن صدر ضوئ ال نه ال تنظر مباشرة الى اي م

تلف عنك

Grade 3 Unit P.2 – Light, Shadows and Mirrors

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Some objects seem bright, but they are only

reflecting (bouncing off) light from elsewhere. So

these are not light sources. These include the

moon, planets, mirrors and shiny objects.

You would not be able to see a reflector of light,

such as a mirror, in a completely dark room. بعض االجسام تعكس الضوء من مصدر اخر و لكنها لست مصادر ضوء مثل القمر و الكواكب و المراا

Class Work

Circle the things which give out light: حول ضع دائرة

مصادر الضوء

Grade 3 Unit P.2 – Light, Shadows and Mirrors

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Survey

What kind of light sources do we use in our

school? ؟ما ه انواع مصادر الضوء المستعملة ف مدرستك

Grade 3 Unit P.2 – Light, Shadows and Mirrors

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How we can see ان نرى كف مكن

1-We see a light source when light from the

source enters our eyes. عندما دخل مصادر الضوء نرى

الضوء اعننا

OR

2-When light from a light source hits an object,

it is reflected (bounces off) and enters our eyes.

This is how we see the object.

.أعيننا إلىنرى األشاء عندما نعكس الضوء من األشاء

Light travels in straight lines

Grade 3 Unit P.2 – Light, Shadows and Mirrors

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Experiment(1)

Objective: to see how light travels in a straight

line خطوط مستقمة كف نتقل الضوء ف

Materials : a torch مصدر ضوء– pieces of newspaper قطعة

baking powder -جردة ربونات الصودوم بك .

1) Spread the newspaper on the floor. فرش الجردة على ا

األرض

2) Make the room dark. اجعل الغرفة مظلمة

3) Turn the torch on. افتح مصدر الضوء خاصتك

4) Shine it across the newspaper. سلطه على الجردة

5) Ask a friend to sprinkle baking soda over the

beam light. Do you see the beam light? دع احد اصدقائك

ترى الضوء ثر البكاربونات على اشعة الضوء هل ن

Draw what you observed سجل مالحظاتك

Grade 3 Unit P.2 – Light, Shadows and Mirrors

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Conclusion األستنتاج:--------------------------------------

---------------------------------------------------------

--------------------------------------------------------------------- -

Experiment (2)

Use a torch and 2 cards with hole cut in them ان من المنتصف و ضعهما بالهيئة التي تمثقوب استعمل مصدر ضوء وبطاقتان

تراها في الصورة باالسفل و غير من الحالة االولى الى الحالة الثانية و سجل .مالحظاتك

What did you learn from this experiment?

?ماذا تعلمت من التجربة

_________________________________________________________________________________________________________________________________

Torch

A B Can you see the light ?----------

.............هل ترى الضوء؟

Torch

A B Can you see the light ?----------

.............هل ترى الضوء؟

Grade 3 Unit P.2 – Light, Shadows and Mirrors

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Light bounces off some materials better than

others هناك اجسام تعكس الضوء اكثر من غرها

Light travels in straight lines. When light

hits an object, it is reflected (bounces

off) and enters our eyes. This is how we

see the object. و دخل الضوء نتقل بخطوط مستقمة

العن و عندها تتم الرؤة

When light from an object is reflected by

a surface, it changes direction. It bounces

off the surface at the same angle as it

hits it. عندما صطدم الضوء ببعض االجسام ستغر

بزاوة معنة مسارها و تنعكس على السطح

Smooth, shiny surfaces such as mirrors

and polished metals reflect light well. Dull

and dark surfaces such as dark fabrics do

not reflect light well. السطوح الملساء كالمراا

لضوء اكثر من غرها مل الداكنة و القماش و الذان ال تعكس ا.عكسان بصورة جدة

Grade 3 Unit P.2 – Light, Shadows and Mirrors

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Reflective surfaces can be very useful.

Mirrors inside cars reflect light to help

drivers see objects behind them. السطوح

العاكسة ف مراا السارات تعكس الضوء و تساعد سائق .ما خلفه دون ان در رأسه الى الخلف السارة على رؤة

‘Cat’s eyes’ on the road reflect light from

car headlamps to help the driver see the

road at night. عون القطط او العاكسات الفسفورة

تعكس الضوء لتساعد السائقن من رؤة الشارع و حدوده

Grade 3 Unit P.2 – Light, Shadows and Mirrors

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Transparent, translucent and opaque

materials ة و نصف شفافة و المعتم االجسام الشفافت

Transparent materials let light pass

through them in straight lines, so that you

can see clearly through them. Glass is an

example of a transparent material. األجسام

الشفافة تسمح بمرور الضوء كامال و بخطوط مستقمة مثل الزجاج

Translucent materials let some light

through, but they scatter the light in all

directions, so that you cannot see clearly

through them. Tissue paper is an example

of a translucent material. نصف الشفافة األجسام

تسمح بمرور بعض الضوء و مكن ان شتته الى اتجاهات مختلفة

Opaque materials do not let any light pass

through them. They block the light. Wood

is an example of an opaque material. الجسم

مثل الخشب مرر الضوء و منع مسارهالمعتم الذي ال

Grade 3 Unit P.2 – Light, Shadows and Mirrors

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Glass is a transparent materialالزجاج هو جسم شفاف

Experiment

Transparent, translucent or opaque materials?

Materials: cardboard ونكارت --tissue paper ورق حمام--

glassزجاج --aluminum foil قصدر- wallpaper ورق جدران-

cling film نصف شفافة شرحة

Use a torch to test and sort these materials استعمل مصدر ضوء لتتفحص المواد السابقة و سجل قراءاتك ف الجدول

Lets light go

through

Clearly مر كل

الضوء

Lets some light

through, not

clearly بعض الضوء

مر

Does not let

light

through at all الضوءال مر

Grade 3 Unit P.2 – Light, Shadows and Mirrors

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Conclusion:الخالصة

Some materials allow light to travel through

them clearly. These materials are called

المواد الت تسمح بمرور الضوء .________________

تسمى Some materials allow some light to travel

through them. These materials are called سمح

.________________بمرور بعض الضوء

Some materials don’t allow light to travel

through them at all. These materials are called

.________________ال سمح بمرور الضوء

Grade 3 Unit P.2 – Light, Shadows and Mirrors

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Shadows الظل

A shadow is made when an object blocks

light. The object must be opaque or

translucent to make a shadow. A

transparent object will not make any

shadow, as light will pass straight through

it. منع تشكل الظل عندما صطدم الضوء بجسم معتم و

و كون منطقة مظلمة ال صلها الضوء مساره

Opaque objects make dark shadows.

Translucent objects make faint shadows. شفاف النصف الجسم أماالجسم المعتم شكل ظال معتما جدا

شكل ظال خففا

If an object is moved closer to the light

source, the shadow gets bigger. اذا اقترب

الجسم من الضوء سوف كبر ظله

If an object is moved further away

from the light source, the shadow gets

smaller. و اذا ابتعد الجسم صغر ظله

Grade 3 Unit P.2 – Light, Shadows and Mirrors

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Observe shadows مالحظة الظالل

1. Use a chart to record your results سجل مالحظاتك

ف الجدول السفل 2. Observe some shadows الحظ بعض الظالل( in the

class room school yard, at your house

etc)

3. Draw the shadow. ارسم الظل

4. Write what object made the shadow. اكتب اسم

الجسم الذي شكل الظلDraw the shadow

ارسم الظلWhat made the shadow

اكتب اسم الجسم الذي شكل الظل

Grade 3 Unit P.2 – Light, Shadows and Mirrors

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Draw a line to match the butterflies with their

shadows صل بن الجسم و ظله

Grade 3 Unit P.2 – Light, Shadows and Mirrors

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Experiment

Light (Shadows)(CW)

When an opaque object is placed between a source

of light and a surface it will cast a shadow. عندما تضع

جسما بين مصدر الضوء و سطح السقوط سوف يتكون لديك ظال

Torch object wall

1. Draw the shape of shadow you think each

object will cast before trying it. ارسم شكل

الظل المتكون

األشياء

Object What is your

prediction ما هو

توقعك

Try it

جرب

Grade 3 Unit P.2 – Light, Shadows and Mirrors

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2. Move the object nearer to the light source and

then further away. What do you notice? حرك الجسم

ماذا تالحظ؟. أبعدهقريبا من الضوء ثم

Draw your results ارسم النتائج

Grade 3 Unit P.2 – Light, Shadows and Mirrors

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Homework

Inquire further

How does the shadow under a tree change during

the day? كيف يتغير الظل تحت الشجرة خالل اليوم

______________________________________

______________________________________

When was the shadow the shortest? متى يكون اقصر ظال

______________________________________

______________________________________

When was the shadow the longest? متى يكون اطول ظال

______________________________________

______________________________________

Grade 3 Unit P.2 – Light, Shadows and Mirrors

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Shadows made by the sun الشمس يتكىن بىجىدالظل

The sun is a very bright natural light

source. It seems to move across the sky

during the day (although it is actually the

Earth that is moving around the sun). تبدو

سماء عرضا لكن ف الحققة لالشمس و كأنها تتحرك و تقطع ا ان االرض ه الت تتحرك و تلف حول نفسها

The sun casts (makes) longest shadows at

the beginning and end of the day, when

the sun is lowest in the sky. The sun casts

shortest shadows at midday, when the sun is

highest in the sky. اطول ظل عند نهاة النهار و بداته و

اقصر ظل ف منتصف النهار عندما تكون الشمس بمنتصف السماء

Midday منتصف النهار

Grade 3 Unit P.2 – Light, Shadows and Mirrors

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Early morning الصباح المبكر

Direct Light Produces More Heat الضوء

أكثرالمباشر ولد حرارة

You need a torch and a piece of paper. تحتاج الى ورقة و

مصدر ضوء

First of all you need to experiment a little

with the flashlight. Put your hand up against

the light source. Feel that it is warm. Move

your hand away just a little. Notice how the

heat is less, but it is still warm. Move your

hand further and nearer the light, tip it so it

is at an angle. Can you feel any differences? اوال

ارفع دك عن ضع دك امام مصدر الضوء و تحسس الحرارة ثمتبرد ن دكالضوء و ستحس ا

……………………………………………………………………………………..

Now you can show the way light produces heat

using your paper. You will also need a watch

and a ruler and a large book

First you need to make sure your paper is cold. Pop

it in the freezer for a few minutes; try to keep it

dry. احفظها جافة الثالجت وبرد الورقة ف

Grade 3 Unit P.2 – Light, Shadows and Mirrors

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Prop the book up at and angle and lay the piece of

paper on it. Lay the torch on another book so that

it shines onto the paper. Feel the paper and notice

when it starts to get warm. Measure three inches

from the light source and mark the spot on the

paper. Keep feeling that bit. How long does it take

to get warm? ضع الورقة على االرض و سلط الضوء علها لفترة من

الزمن على ان كون مصدر الضوء ثابتا ف بعد معن دون ان تحرك و و تحسب الفترة الزمنة الى ان تسخن علك ان تقس هذه المسافة الثابتة

الورقة

Draw here

Write your conclusion: الخالصة باكت

---------------------------------------------------------

---------------------------------------------------------

Grade 3 Unit P.2 – Light, Shadows and Mirrors

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---------------------------------------------------------

---------------------------------------------------------

Check point

Q1: Complete the concept map: اكمل المخطط التال

Light

source

Grade 3 Unit P.2 – Light, Shadows and Mirrors

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Q2: Complete:

Sunlight can be blocked to form--------------- ..........................مسار ضوء الشمس ب ممكن ان منع

Light is ----------------from mirrors and other

surfaces. على المراا ..........................الضوء

Light travels in ------------------line. الضوء نتقل ف

...........................خطوط The nearer an object is to a light source the

____________ is the shadow. اقتراب الضوء من ب

..................................الجسم كون الظل The further an object is from a light source

the ____________ the shadow. ابتعاد الضىء عه

.......................................الجسم يكىن الظل Light travels in ____________ __________

from a __________ _________. نتقل الضوء

.......................من .........................ف Some sources of light are ___________

_____________ __________بعض مصادر الضوء ه

The moon is not a ___________ of

______________. It reflects light. القمر عكس

.......................................الضوء و لس Darkness is the absence of الظالم معناهانه ال وجد

________________.

A shadow is caused because light cannot travel

round _______________. الظل تكون النه الضوء ال

.............................لتف حول

Grade 3 Unit P.2 – Light, Shadows and Mirrors

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We see when light _______________ our

تحدث الرؤا عندما ._____________

When light hits an object it is reflected. A

shiny object reflects _________ light than a

dull object. من المعتمة .............الضوء لالمعة تعكسا األجسام

When light is reflected it changes انعكاس الضوء

_________________عن

The nearer an object is to a light source the

____________ is the shadow. قرب الجسم من الضوء ب

.........................كون الظل The further an object is from a light source

the ____________ the shadow. بعد الجسم عن

...........كون الظل الضوء

Grade 3 Unit P.2 – Light, Shadows and Mirrors

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Q3: Name two objects that will block light. اعط مثاالن

مسار الضوء الت تمنع لألجسام ---------------------------------------------------------

---------------------------------------------------------

Q4: What is a magnifier? Draw it. المكبرة ارسمهاما ه

Grade 3 Unit P.2 – Light, Shadows and Mirrors

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Further investigation

Can we use magnifiers to focus light???????

Q6: Draw the sun in the following picture ارسم الضوء

المار ف هذه العدسة المكبرة